V10 Manual - extra rare
#61
10-09-2005, 12:36 AM
Good post there Fredvon - I especially liked this bit of information;
Frank also is not aware that the 5R110 is computer controlled and the torque converter has a well designed lock and un lock logic. When a load is sensed it can unlock, allow torque to multiply and prevent the need for a down shift.
Question - when this particular action occurs, is it something which can be felt? I mean, is there any discernable difference to the operator about the truck's behavior during this locking and unlocking action? Also, how does this sort of thing effect long term durability? I understand the transmission is designed to do this just figured I'd ask. Certainly seems automatic transmissions have come a long way.
Anyway, I still don't understand how an auto is going to put more torque to the ground at any given time than a manual will. What are you suggesting I am not telling here? It's my understanding that a torque convertor does just what it says it does. It dosent multiply engine torque, it simply creates a gear reduction factor within the transmission while causing the engine to spin a higher rpm. Of course the higher engine RPM will increase torque input. So here's another scenario;
V10/5r110 = V10 at 2200 rpm producing 420 lbft input torque to 3.10 first gear multiplied by a factor of 1.89 (-) 20% heat loss = 420 lbft x 4.68:1 1st gear = 1965 lbft
(-) 5% mechanical loss x (insert rear axle ratio) = available rear wheel torque.
V10/ZF6speed = V10 engaging clutch at 1200 rpm producing 370 lbft input torque to 5.79 1st gear ratio = 370 lbft x 5.79:1 1st gear = 2142 lbft (-) 10% mechanical loss x (insert rear axle ratio) = available rear wheel torque.
Rear axle is not important as we can see with these numbers that so long as they are the same, the 6speed will be putting down more torque. And after the clutch is fully engaged - 5.79 will spin that V10 up right to peak RPM if need be - now your talking equal input torque AND deeper gears for the manual. But whats more important IMO,
is that it keeps multiplying by a fixed number - an auto dosent typically do this.
This advantage is part of what I base my comment on more durability/greater resistance to heat damage on. I'm not talking of pulling around tandem utility trailers or 30 foot RV trailers - granted a manuals greater resistance to heat applies here too, but it is less important since these types of loads really don't tax these vehicles in an extreme sort of way. In consistent low speed heavy hauling type situations (like using a truck for pulling hay wagons from one part of the farm to the other all day, or lugging up two bobcats and a variety of other equipment on a heavy equipment trailer off road to construction sites everyday- that's going to take a toll on an auto over time).
Thanks for the compliment Wrench.
Frank also is not aware that the 5R110 is computer controlled and the torque converter has a well designed lock and un lock logic. When a load is sensed it can unlock, allow torque to multiply and prevent the need for a down shift.
Question - when this particular action occurs, is it something which can be felt? I mean, is there any discernable difference to the operator about the truck's behavior during this locking and unlocking action? Also, how does this sort of thing effect long term durability? I understand the transmission is designed to do this just figured I'd ask. Certainly seems automatic transmissions have come a long way.
Anyway, I still don't understand how an auto is going to put more torque to the ground at any given time than a manual will. What are you suggesting I am not telling here? It's my understanding that a torque convertor does just what it says it does. It dosent multiply engine torque, it simply creates a gear reduction factor within the transmission while causing the engine to spin a higher rpm. Of course the higher engine RPM will increase torque input. So here's another scenario;
V10/5r110 = V10 at 2200 rpm producing 420 lbft input torque to 3.10 first gear multiplied by a factor of 1.89 (-) 20% heat loss = 420 lbft x 4.68:1 1st gear = 1965 lbft
(-) 5% mechanical loss x (insert rear axle ratio) = available rear wheel torque.
V10/ZF6speed = V10 engaging clutch at 1200 rpm producing 370 lbft input torque to 5.79 1st gear ratio = 370 lbft x 5.79:1 1st gear = 2142 lbft (-) 10% mechanical loss x (insert rear axle ratio) = available rear wheel torque.
Rear axle is not important as we can see with these numbers that so long as they are the same, the 6speed will be putting down more torque. And after the clutch is fully engaged - 5.79 will spin that V10 up right to peak RPM if need be - now your talking equal input torque AND deeper gears for the manual. But whats more important IMO,
is that it keeps multiplying by a fixed number - an auto dosent typically do this.
This advantage is part of what I base my comment on more durability/greater resistance to heat damage on. I'm not talking of pulling around tandem utility trailers or 30 foot RV trailers - granted a manuals greater resistance to heat applies here too, but it is less important since these types of loads really don't tax these vehicles in an extreme sort of way. In consistent low speed heavy hauling type situations (like using a truck for pulling hay wagons from one part of the farm to the other all day, or lugging up two bobcats and a variety of other equipment on a heavy equipment trailer off road to construction sites everyday- that's going to take a toll on an auto over time).
Thanks for the compliment Wrench.
Last edited by sinister73; 10-09-2005 at 12:43 AM.
#62
10-09-2005, 01:46 AM
Alright Frank now we have some factors to deal with
First your question on the lock up TC. You never really sense the action during normal acceleration. The computer senses the difference between the two halve and when it is less than 5% it will lock. Another sensor determines load and will un lock if a command to shift is immanent. Best time to see her work is in cruise control and climbing slight grade. Watching the Tach when she un locks you can see a 150-250rpm increase but no change in MPH. It is designed to not bang together and can unlock in a hurry and down shift all in the same action, say in a panic deceleration on the brakes hard.
Not sure where you keep factoring in the 1.89 figure so let me tell you this
A torque Converter is not a Linear device it does not slip and generate pressure at a constant rate, as the two halves become different speeds the amount of torque generated increases exponentially. Say at a difference of 100 rpm we get 100 lbs in and 110lbs out then at 200 rpm difference a linear device would increase the output at the same ratio 10% so on and so on where the input torque is increased on the output side in a constant slope. But since it multiplies logarithmically the out put is a curve that gets steeper as the difference between the input and output halves rotate.
The engineers use a lengthy stream of math to do a fancy average calculation and different design TCs have different multiplication factors. I do not know the exact factor for this series of lock up TCs but typically 23% is normal.. but remember this is the average much of time the factor is less then 5% (when two halves are near same speed) and there are times when the difference in rotational speeds is very large the factor can approach 50% so 100ftlb in yields 150ftlbs out
Gear reduction and torque multiplication are not direct math leverages either. Dimensions can radically effect total torque multiplication a 4 to 1 ratio can be 32 tooth gear turning 128 tooth gear and will have a different mechanical advantage then a 4 tooth gear turning a 16 tooth gear
If you have a gear set that is a 4 to 1 and you apply 100ftlbs you do not get 400ftlbs out due to the above fact AND if they are right angle gears there is a physical loss from drag and there is a calculated loss for every 90degrees the power get turned. These losses are not great (under 5%) but they are additive and compound each other. The planetary sets eliminate much of the angular loss and slightly increase the parasitic loss (more moving parts) and usually have greater mechanical advantage due to physical size (many more teeth)
well Frank it is 1:38 Am Sunday morning here and I can't put any more coherent sentences together... ponder some of these thougts and keep after me to defend the TorqShift
It is a great exercise to try am remember all the crap they taught me in Tank Automotive course... you just gots to know some smart *** soldier asked the instructor why the hell we had auto trannies in big *** tanks.... bad move, I was the poor sap who had to diagram power flows for an hour before he let me do my 50 push ups and get my as back to my seat!
First your question on the lock up TC. You never really sense the action during normal acceleration. The computer senses the difference between the two halve and when it is less than 5% it will lock. Another sensor determines load and will un lock if a command to shift is immanent. Best time to see her work is in cruise control and climbing slight grade. Watching the Tach when she un locks you can see a 150-250rpm increase but no change in MPH. It is designed to not bang together and can unlock in a hurry and down shift all in the same action, say in a panic deceleration on the brakes hard.
Not sure where you keep factoring in the 1.89 figure so let me tell you this
A torque Converter is not a Linear device it does not slip and generate pressure at a constant rate, as the two halves become different speeds the amount of torque generated increases exponentially. Say at a difference of 100 rpm we get 100 lbs in and 110lbs out then at 200 rpm difference a linear device would increase the output at the same ratio 10% so on and so on where the input torque is increased on the output side in a constant slope. But since it multiplies logarithmically the out put is a curve that gets steeper as the difference between the input and output halves rotate.
The engineers use a lengthy stream of math to do a fancy average calculation and different design TCs have different multiplication factors. I do not know the exact factor for this series of lock up TCs but typically 23% is normal.. but remember this is the average much of time the factor is less then 5% (when two halves are near same speed) and there are times when the difference in rotational speeds is very large the factor can approach 50% so 100ftlb in yields 150ftlbs out
Gear reduction and torque multiplication are not direct math leverages either. Dimensions can radically effect total torque multiplication a 4 to 1 ratio can be 32 tooth gear turning 128 tooth gear and will have a different mechanical advantage then a 4 tooth gear turning a 16 tooth gear
If you have a gear set that is a 4 to 1 and you apply 100ftlbs you do not get 400ftlbs out due to the above fact AND if they are right angle gears there is a physical loss from drag and there is a calculated loss for every 90degrees the power get turned. These losses are not great (under 5%) but they are additive and compound each other. The planetary sets eliminate much of the angular loss and slightly increase the parasitic loss (more moving parts) and usually have greater mechanical advantage due to physical size (many more teeth)
well Frank it is 1:38 Am Sunday morning here and I can't put any more coherent sentences together... ponder some of these thougts and keep after me to defend the TorqShift
It is a great exercise to try am remember all the crap they taught me in Tank Automotive course... you just gots to know some smart *** soldier asked the instructor why the hell we had auto trannies in big *** tanks.... bad move, I was the poor sap who had to diagram power flows for an hour before he let me do my 50 push ups and get my as back to my seat!
#63
10-14-2005, 09:02 PM
Senior User
Join Date: Feb 2005
Location: New Jersey Shore
Posts: 167
Likes: 0
Received 0 Likes
on
0 Posts
All that said, I'm sticking to my Manual Trans.
I've never had a bit of trouble with anyone I've ever owned. If you think maintenance/repair costs are cheaper on an auto, you are sadly mistaken. No valve bodies to deal with, no filters, same oil but much less of it. Sounds to me like Ford engineers have defied all of Einstien's theories and created a Torque Converter that creates its own energy.
I would also like to argue the point that chain drive transfer cases are not as dependable as the old Gear to Gear units. I've taken apart the old ones with 500,000 miles on them and was convinced they could make it another 500,000 with nothing but an oil change. I've seen a bunch (my own included) of chain units wear out with 175,000 and either need to replace the chain that had stretched or it had broken and gone right through the bottom of the case. Just something to ponder.
Fight the good fight Sinister!
I've never had a bit of trouble with anyone I've ever owned. If you think maintenance/repair costs are cheaper on an auto, you are sadly mistaken. No valve bodies to deal with, no filters, same oil but much less of it. Sounds to me like Ford engineers have defied all of Einstien's theories and created a Torque Converter that creates its own energy.
I would also like to argue the point that chain drive transfer cases are not as dependable as the old Gear to Gear units. I've taken apart the old ones with 500,000 miles on them and was convinced they could make it another 500,000 with nothing but an oil change. I've seen a bunch (my own included) of chain units wear out with 175,000 and either need to replace the chain that had stretched or it had broken and gone right through the bottom of the case. Just something to ponder.
Fight the good fight Sinister!
#64
10-14-2005, 09:21 PM
#65
10-14-2005, 10:35 PM
I thought that I was passionate about manual trannys until I read some of Sinisters posts. In the last few days I have discovered that there are others who appreciate the beauty of manual systems (trannys, transfer cases, hubs etc) and I feel the need to chime in here with my kindred spirits. Bottom line, as stated by several others, an automatic will never match a manual in reliability, dependability and versatility. And the more "advanced" they get with computer controls and such the scarier they get in my mind (and I have a B.S. degree in electronic engineering). My reliability class taught me that the more components you have in a system the more likely you are to have a failure. 25 years in manufacturing taught me that the more elaborate the design the more expensive it is to repair and/or replace. As for the torque multiplying abilities of the torque converter this has got to be one of the most misunderstood/misrepresented concepts in automotive history. The engine is the power plant and it produces a finite amount of torque at a given speed. Multiplying the engine's torque comes at the expense of reduced rpm. This is usually accomplished through gear reduction although a torque converter can do this in a fashion. The only method I think you could use to demostrate this would be to weigh down the truck on nice new sticky pavement such that the tires could not possibly rotate and hook a chain to a large oak tree stump that can not be moved. In this case you either fry the clutch or kill the engine in a manual whereas the auto would actually be consistently applying serious torque to the rear wheels (albeit in vain). Since I generally try not to attach my truck to things that don't move I prefer to multiply the torque with first gear. I can't tell you how many times I pulled a my truck and camper out of the holes I dug to level it at little more than an idle in first gear while my auto equipped comrades had to apply some serious go pedal before the truck would move. That torque converter was multiplying the torque as hard as it could to get to where granny gear did it with ease. Also, where in a manual trans is the power rotated 90 degrees? I don't know that gears running on parallel shafts could be considered as such. An auto does have the occasional advantage but overall the manual has many more. The automatics may be winning in the sales arena but this is only due to the convenience factor, just like electronic 4WD.
#66
10-15-2005, 09:22 AM
If you CHOOSE the PSD over the 3v V10 simply because you desire and want a diesel motor and accept it's costs, limitations, and it's benefits that is fine and most folks accept that reasoning. It is when the PSD guy tries to tell a potential new owner that he MUST not consider the 3v V10 because of xxxx and then goes on to describe a bunch of subjective BS using flawed logic, distorted facts, and out right mis-information that we V10 owners are willing to jump in and cry BS!
What is different about the electronic 4x4 system or the transmission.... ??
You folks who PREFER the ZF forced me to play devils advocate for the same reasons. Some of you want to make arguments trying to describe why the manual is superior... But not one of you stated any typical road condition, tow or haul load, or specific capability where the ZF is absolutely necessary to get the job done.
If I was arguing this FOR the ZF I would have to say that for a truck I intended to buy with the MOST bang for the buck the free manual trans and the $510 V10 option is the best configuration possible if you are very good at clutching and shifting. If I need a play truck and intend to drag race, I MIGHT consider the ZF more for the fun and Macho factor. If my truck was mostly farm use in fields, then the ZF gives me an edge in crawling control creeping along a baler hauling a trailer. If my new truck was going to see a lot of back woods roads and fair anount of 4x4 time then the ZF is probably a better choice. If my truck was always used for country driving with little or no city use then I MIGHT choose the ZF for ease of maintenance, reliability and simplicity. In any of those cases I think I have to also factor Fun, and adrenalin. Nothing the 5R110 does can generate the fun and adrenalin like clutching and stuffing! With the exception of the low cost truck, or the farm truck following a baler, or the Fun factor, none of those examples means the 5R110 is an inferior trany or can not do the mission.
If you want to compare the ZF to any trans of days gone by that is OK but not relevant
Usually the start of the threads like this, is someone wanting opinions about the ZF and the 4R100 or 5R110 because they are trying to decide on some purchase decision, and the lack of ZF mated to a V10 on the lot has them thinking of a compromise.
In this case we need to know what the person asking the question intended use is. Then we offer OBJECTIVE and SUBJECTIVE comments on the capabilities and limitations of either choice, just that simple. Adding that you prefer the manual or that you had bad experiences with auto tranies is relevant. It lets the question asker know your bias. Nothing wrong with saying what you prefer and why.
If you have followed my writings for any short amount of time, you will notice that most of the time I only jump in when by BS detector starts vibrating.
I have presented to the technical merits of the 5R110 in this case, if you want to continue arguing about technically or dynamically one or other of these two available transmissions are better I am happy to oblige...
If you want to argue fun factor or adrenalin then that is different. I love a hand shaker.
And if you want to discuss reliability and durability that can take another turn because I have a lot of experience on those issues from a commercial and personal ownership perspective.
But I will state for the 4th or 5th time in this thread that I like manual tranies and like the PSD, there are times when I recommend the hand shaker.
All I ever expect here in the V10 forum is intellectual honesty. Saying that a PSD is the better choice because the extra cost is rewarded at re-sale is NOT the whole truth. Same with saying out right that auto trannies are a POS and the manual is a better tow trans or implying that there is no maintenance associated with owning a manual.
What is different about the electronic 4x4 system or the transmission.... ??
You folks who PREFER the ZF forced me to play devils advocate for the same reasons. Some of you want to make arguments trying to describe why the manual is superior... But not one of you stated any typical road condition, tow or haul load, or specific capability where the ZF is absolutely necessary to get the job done.
If I was arguing this FOR the ZF I would have to say that for a truck I intended to buy with the MOST bang for the buck the free manual trans and the $510 V10 option is the best configuration possible if you are very good at clutching and shifting. If I need a play truck and intend to drag race, I MIGHT consider the ZF more for the fun and Macho factor. If my truck was mostly farm use in fields, then the ZF gives me an edge in crawling control creeping along a baler hauling a trailer. If my new truck was going to see a lot of back woods roads and fair anount of 4x4 time then the ZF is probably a better choice. If my truck was always used for country driving with little or no city use then I MIGHT choose the ZF for ease of maintenance, reliability and simplicity. In any of those cases I think I have to also factor Fun, and adrenalin. Nothing the 5R110 does can generate the fun and adrenalin like clutching and stuffing! With the exception of the low cost truck, or the farm truck following a baler, or the Fun factor, none of those examples means the 5R110 is an inferior trany or can not do the mission.
If you want to compare the ZF to any trans of days gone by that is OK but not relevant
Usually the start of the threads like this, is someone wanting opinions about the ZF and the 4R100 or 5R110 because they are trying to decide on some purchase decision, and the lack of ZF mated to a V10 on the lot has them thinking of a compromise.
In this case we need to know what the person asking the question intended use is. Then we offer OBJECTIVE and SUBJECTIVE comments on the capabilities and limitations of either choice, just that simple. Adding that you prefer the manual or that you had bad experiences with auto tranies is relevant. It lets the question asker know your bias. Nothing wrong with saying what you prefer and why.
If you have followed my writings for any short amount of time, you will notice that most of the time I only jump in when by BS detector starts vibrating.
I have presented to the technical merits of the 5R110 in this case, if you want to continue arguing about technically or dynamically one or other of these two available transmissions are better I am happy to oblige...
If you want to argue fun factor or adrenalin then that is different. I love a hand shaker.
And if you want to discuss reliability and durability that can take another turn because I have a lot of experience on those issues from a commercial and personal ownership perspective.
But I will state for the 4th or 5th time in this thread that I like manual tranies and like the PSD, there are times when I recommend the hand shaker.
All I ever expect here in the V10 forum is intellectual honesty. Saying that a PSD is the better choice because the extra cost is rewarded at re-sale is NOT the whole truth. Same with saying out right that auto trannies are a POS and the manual is a better tow trans or implying that there is no maintenance associated with owning a manual.
#68
10-15-2005, 01:45 PM
Nice to hear from a few fellow manual transmission advocates like myself. I've been fighting the good fight and now I feel like the cavalry has arrived - just a few days late and a few dollars short...lol.
OK Fred I'll bite. You seem to insist that this particular thread occured a certain way.
According to you, the original poster came in looking for advice regarding automatics and their advantages vs manuals and their advantages. I then jumped in subjecting this man to my subjective BS, flawed logic, and outright misinformation - at which point you decided to enter in and set things straight...thus, saving the day.
Seems to me a case of an overly zealous automatic owner forcing his opinion upon others - himself being wholey incapable of keeping his nose from where it does not belong. This owner then goes on to distort everything - even the original poster's questions and statements.
I'll repeat (for the 4th or 5th time) this man asked nothing about your torqueshift automatic. He made it obvious that he could care less. He asked nothing about a diesel either. If someone had come in bashing the diesel a bit unfairly and gave his own biased opinion as to why the original poster had made the right decision in going with the V10 - he would not be admonished here for it - certainly not from you.
This is a bit different since it's the V10 forum and there is no such thing as a "manual transmission" forum here on FTE. Manual vs auto comes up in all forums. All the same it is still similar in the sense that this PARTICULAR thread belongs to manual transmissions.
The original poster did not ask for a debate on why the automatic is so superior in so many different ways. His decision was made from the getgo - I merely did what any V10 guy might do if the question were posed about a guy wanting to find a V10 on the lot, and being unwilling to accept a diesel alternative. Yes I over reacted. Yes I made general statements which were unfair to automatic transmissions - guess what? The original poster shares these same views - flawed or not. It's not a topic which is open for debate and this man indicated he had no intention of making any compromise.
The only BS going on here is your hijacking of this thread to the point that it's not about what it was anymore. Seems to me your the one with a personal axe to grind - perhaps your having second thoughts on your own purchase. Not easy second guessing yourself is it? Afterall, you say we are forcing you into the role of devil's advocate. Funny no other automatic owners felt compelled to take on this role - they simply state their reasons for their choices and move on - I guess they have nothing to prove.
You also say you love manuals yourself and have driven them for many years. Now that you have aquired the auto yourself, perhaps you feel as if your confidence has been misplaced?
For whatever reason, it seems no longer acceptable to you for anyone to own a manual for any stated reason other than admitting the enjoyment / fun / macho factor of it. It seems your attempting to force a profile of this sort upon us. So let's get to the heart of it all then. Let's profile all automatic owners as well. I can sum it up in one word for you so repeat after me;.....LAZY. It's certainly NOT ANY of the advantageous gibberish you've been spouting in favor of the auto which is responsonsible for the vast number of trucks equipped with auto transmissions.
I guess you are one of the rare noted exceptions.
It is this same lazy mentality which keeps people waiting in an ungodly drivethru line when the restaurant has no line inside. I guess the wait is worth not having to get off your ***. And I'd bet the majority of those asses are sitting in vehicles equipped with auto transmissions. Like my profiling attempt so far? I admit my analogy is a bit crude, but dosent it qualify as intellectual honesty? I mean anyone who is reasonably intelligent knows that autos sell because they facilitate laziness. Honesty is admitting it. A spade is a spade you know.
OK Fred I'll bite. You seem to insist that this particular thread occured a certain way.
According to you, the original poster came in looking for advice regarding automatics and their advantages vs manuals and their advantages. I then jumped in subjecting this man to my subjective BS, flawed logic, and outright misinformation - at which point you decided to enter in and set things straight...thus, saving the day.
Seems to me a case of an overly zealous automatic owner forcing his opinion upon others - himself being wholey incapable of keeping his nose from where it does not belong. This owner then goes on to distort everything - even the original poster's questions and statements.
I'll repeat (for the 4th or 5th time) this man asked nothing about your torqueshift automatic. He made it obvious that he could care less. He asked nothing about a diesel either. If someone had come in bashing the diesel a bit unfairly and gave his own biased opinion as to why the original poster had made the right decision in going with the V10 - he would not be admonished here for it - certainly not from you.
This is a bit different since it's the V10 forum and there is no such thing as a "manual transmission" forum here on FTE. Manual vs auto comes up in all forums. All the same it is still similar in the sense that this PARTICULAR thread belongs to manual transmissions.
The original poster did not ask for a debate on why the automatic is so superior in so many different ways. His decision was made from the getgo - I merely did what any V10 guy might do if the question were posed about a guy wanting to find a V10 on the lot, and being unwilling to accept a diesel alternative. Yes I over reacted. Yes I made general statements which were unfair to automatic transmissions - guess what? The original poster shares these same views - flawed or not. It's not a topic which is open for debate and this man indicated he had no intention of making any compromise.
The only BS going on here is your hijacking of this thread to the point that it's not about what it was anymore. Seems to me your the one with a personal axe to grind - perhaps your having second thoughts on your own purchase. Not easy second guessing yourself is it? Afterall, you say we are forcing you into the role of devil's advocate. Funny no other automatic owners felt compelled to take on this role - they simply state their reasons for their choices and move on - I guess they have nothing to prove.
You also say you love manuals yourself and have driven them for many years. Now that you have aquired the auto yourself, perhaps you feel as if your confidence has been misplaced?
For whatever reason, it seems no longer acceptable to you for anyone to own a manual for any stated reason other than admitting the enjoyment / fun / macho factor of it. It seems your attempting to force a profile of this sort upon us. So let's get to the heart of it all then. Let's profile all automatic owners as well. I can sum it up in one word for you so repeat after me;.....LAZY. It's certainly NOT ANY of the advantageous gibberish you've been spouting in favor of the auto which is responsonsible for the vast number of trucks equipped with auto transmissions.
I guess you are one of the rare noted exceptions.
It is this same lazy mentality which keeps people waiting in an ungodly drivethru line when the restaurant has no line inside. I guess the wait is worth not having to get off your ***. And I'd bet the majority of those asses are sitting in vehicles equipped with auto transmissions. Like my profiling attempt so far? I admit my analogy is a bit crude, but dosent it qualify as intellectual honesty? I mean anyone who is reasonably intelligent knows that autos sell because they facilitate laziness. Honesty is admitting it. A spade is a spade you know.
Last edited by sinister73; 10-15-2005 at 02:31 PM.
#69
10-15-2005, 01:47 PM
Part two
I admit automatics have their place. For a minute here, let's think of all the fat posers sitting in their vehicles for 20 minutes or better waiting on a McDonalds drivethru line to move along. They can see the restaurant is empty on the inside. Still they wait it out hoping that the line will soon move faster. Or they make conversation to help pass the time away. These people are being lazy. On top of this they do not have enough intelligence to even realise it. Do we really want these sorts of people attempting to shift gears and syncronise clutches with gear changes or acceleration?
Enter the automatic transmission. Suddenly these people with lazy bodies and equally lazy minds are removed from the equation of shifting gears and doing anything other than steering, giving it gas or stepping on the brake occasionally. The truck is doing itself a favor by removing these uninitiated people from the driving equation as much as possible.
Of course not all automatic owners are stupid fat people. Some can drive a manual as well as anyone - but they are too lazy to be bothered with it. For those who can drive a stick very well - but choose not to, the automatic offers them no advantage other than to facilitate their laziness. For those that are too stupid to drive a manual correctly, or never learned how - what's true for everyone is that an auto offers a real advantage over an improperly used manual.
Torque multiplication is an often heard excuse made by some to rationalise their laziness (seems everyone tries to rationalize being lazy at some time or another)- hence their choice of an auto transmission. Nobody buys an auto for torque multiplication - really they buy it for the fact that you only need to put it in gear and hit the gas pedal.
Really auto manufacturers push the automatic for profits. Plain and simply put - this is the truth. The six speed is considered the standard available transmission. Ford has to pay ZF for this outsourced gear box. They cannot make money by giving away a "free" manual transmission - so you'd better believe it's been priced into the base cost of the truck for those who do opt for the standard transmission.
The auto is all profit. The price of the six speed which is figured into the base vehicle cost is not credited back. Yet Ford does not have to pay for the gear box. They then charge an additional 1700.00 for a transmission which is built in-house and costs them much less to produce per unit than the 6 speed costs to buy per unit. All profit. In essence, you are giving them back the gear box, allowing them to keep the peddling fee on it, AND paying 1700.00 for their cheaper to produce automatic - this is'int brain science here. They want you to ante up for the auto.
The diesel option is different from the automatic, since unlike the automatic which is produced in-house, the diesel must be outsourced - like the manual transmission. And like the manual transmission, Ford must pay MORE for it. Much more than it costs them to produce an engine in-house. On top of this, if a warranty problem should arise, Ford must pay for replacement parts which they do not manufacture. These parts are much more expensive to replace because of this. True, Ford gets to keep the base 5.4L gas engine, but since it is produced in-house, they arent saving that much.
So unlike the auto which is a situation of replacing an outsourced product with one manufactured in-house - creating much more profit and lesser cost, the diesel is a situation of replacing an in-house product with an outsourced one - a very expensive one at that. Autos are all profit - diesels are not, but demand dictates that Ford will keep offering them en masse or lose market share. I dare say the Super Duty would not even sell as many heavy duty units as Dodge does were there no diesel option - let alone the GM clones. So if the others are selling lots of diesels - Ford better too.
Let's get a little technical - starting with this statement I've been pondering for a little while;
"Frank also is not aware that the 5R110 is computer controlled and the torque converter has a well designed lock and un lock logic. When a load is sensed it can unlock, allow torque to multiply and prevent the need for a down shift."
Sounds like slippage to me. Sounds like a good way of creating lots of heat and causing potential cover warpage, burned linings, and damaged valves and ports if whatever load you have in mind is enough to cause this to be happening on a consistent basis.
This also begs the question - how can an automatic possibly get the same mileage under load as a manual if this magic is happening? When a clutch is fully released on a manual the efficiency is 100% correct? Your not getting near the efficiency from a torque converter which is consistently unlocking itself to multiply torque under load. So your going to get equal or better mileage with an auto when the efficiency is well below the 100% the manual is getting under the same load? I mean, you say it's intentionally designed to allow slippage right? Slippage creates more heat and less efficiency from what the experts over at ATS have to say on the matter;
------------------
Efficiency
Efficiency, according to industry definition, is simply the ratio of the impeller speed to the turbine speed. If the engine is running at 2000 RPM, the impeller is directly connected to the engine so it is also rotating at 2000 RPM. If the turbine were spinning at 1800 RPM, this would be defined as a 90% (1800/2000=90%) efficient torque converter.
Efficiency numbers are very misleading because the number depends on many factors including load, vehicle speed and torque converter design. At one extreme, picture your truck sitting at a stop light with the engine idling at 750 RPM. The impeller is turning at 750 RPM, but the turbine isn´t moving. 750/0=0%. At a stop light the torque converter is zero percent efficient.
A more typical example would be an engine running at 2000 rpm at highway speed and a turbine speed of 1800 rpm resulting in a 90% rating. This is the method that current efficiency ratings are determined. However, this methodology is flawed. An example of the other extreme illustrates this. Imagine a truck going down a big grade with no lockup clutch and using an exhaust brake. The engine will be holding the truck back and the turbine will actually be spinning faster than the impeller. In this case if the engine was at 1800 rpm and the turbine was at 2000 rpm, the efficiency would be 2000/1800=111%. The truth is no mechanical device can be more than 100% efficient, so there is obviously a problem with conventional torque converter efficiency ratings. In addition, we have just illustrated three cases where the same truck is subjected to three different loads, resulting in three different efficiency ratings.
The point is, many manufacturers like to claim high efficiency ratings, but unless each torque converter is compared under the exact same standardized conditions, these efficiency numbers are meaningless. Don´t be fooled by reported efficiency ratings. For all practical purposes these numbers can´t be compared between manufacturers and are simply marketing propaganda.
Torque converter efficiency really is the ability of the stator to "get out of the way" and not impede ATF flow when the impeller and turbine are spinning at approximately the same speed. 100% efficiency can only be achieved when in lockup with no lockup clutch slippage.
------------------
In fact since we've last parted on this subject I've done quite a bit of reading on various torque converters and the like. These guys know what they're talking about - and they all agree the OEM manufacturers produce junk. There are so many ways in which to improve on current OEM automatics to make them more reliable and bullet proof. I'd bet an ATS modified tranny can do eveything a ZF can do except offer the same crawl ratio or potential control for a very certain set of limited circumstances - this comes at a premium cost however, and the Torqueshift is no ATS tranny - not even close. The 4r100 is even further off.
As to low end torque - the manuals don't multiply torque like an auto does - HENCE the reason for that ultra low gear for moving heavy loads - all in all they get just as much torque to the ground - if not much more, due to the fact that the automatic is trading efficiency for torque multiplication and is geared much higher (lower numerically)- period.
Speaking strictly of factory transmissions. Speaking strictly of the two specific OEM transmissions offered in the Ford Super Duty. And speaking only of people who can drive either type very competently - if all these criteria are met, I see more advantage for the manual over the auto. This goes for durability, reliability, ease
of maintenance, and cost efficiency.
I can summise two things from here; 1.) I'm never at a loss for words when provoked.
2.) All of this should get your goad pretty good.
I admit automatics have their place. For a minute here, let's think of all the fat posers sitting in their vehicles for 20 minutes or better waiting on a McDonalds drivethru line to move along. They can see the restaurant is empty on the inside. Still they wait it out hoping that the line will soon move faster. Or they make conversation to help pass the time away. These people are being lazy. On top of this they do not have enough intelligence to even realise it. Do we really want these sorts of people attempting to shift gears and syncronise clutches with gear changes or acceleration?
Enter the automatic transmission. Suddenly these people with lazy bodies and equally lazy minds are removed from the equation of shifting gears and doing anything other than steering, giving it gas or stepping on the brake occasionally. The truck is doing itself a favor by removing these uninitiated people from the driving equation as much as possible.
Of course not all automatic owners are stupid fat people. Some can drive a manual as well as anyone - but they are too lazy to be bothered with it. For those who can drive a stick very well - but choose not to, the automatic offers them no advantage other than to facilitate their laziness. For those that are too stupid to drive a manual correctly, or never learned how - what's true for everyone is that an auto offers a real advantage over an improperly used manual.
Torque multiplication is an often heard excuse made by some to rationalise their laziness (seems everyone tries to rationalize being lazy at some time or another)- hence their choice of an auto transmission. Nobody buys an auto for torque multiplication - really they buy it for the fact that you only need to put it in gear and hit the gas pedal.
Really auto manufacturers push the automatic for profits. Plain and simply put - this is the truth. The six speed is considered the standard available transmission. Ford has to pay ZF for this outsourced gear box. They cannot make money by giving away a "free" manual transmission - so you'd better believe it's been priced into the base cost of the truck for those who do opt for the standard transmission.
The auto is all profit. The price of the six speed which is figured into the base vehicle cost is not credited back. Yet Ford does not have to pay for the gear box. They then charge an additional 1700.00 for a transmission which is built in-house and costs them much less to produce per unit than the 6 speed costs to buy per unit. All profit. In essence, you are giving them back the gear box, allowing them to keep the peddling fee on it, AND paying 1700.00 for their cheaper to produce automatic - this is'int brain science here. They want you to ante up for the auto.
The diesel option is different from the automatic, since unlike the automatic which is produced in-house, the diesel must be outsourced - like the manual transmission. And like the manual transmission, Ford must pay MORE for it. Much more than it costs them to produce an engine in-house. On top of this, if a warranty problem should arise, Ford must pay for replacement parts which they do not manufacture. These parts are much more expensive to replace because of this. True, Ford gets to keep the base 5.4L gas engine, but since it is produced in-house, they arent saving that much.
So unlike the auto which is a situation of replacing an outsourced product with one manufactured in-house - creating much more profit and lesser cost, the diesel is a situation of replacing an in-house product with an outsourced one - a very expensive one at that. Autos are all profit - diesels are not, but demand dictates that Ford will keep offering them en masse or lose market share. I dare say the Super Duty would not even sell as many heavy duty units as Dodge does were there no diesel option - let alone the GM clones. So if the others are selling lots of diesels - Ford better too.
Let's get a little technical - starting with this statement I've been pondering for a little while;
"Frank also is not aware that the 5R110 is computer controlled and the torque converter has a well designed lock and un lock logic. When a load is sensed it can unlock, allow torque to multiply and prevent the need for a down shift."
Sounds like slippage to me. Sounds like a good way of creating lots of heat and causing potential cover warpage, burned linings, and damaged valves and ports if whatever load you have in mind is enough to cause this to be happening on a consistent basis.
This also begs the question - how can an automatic possibly get the same mileage under load as a manual if this magic is happening? When a clutch is fully released on a manual the efficiency is 100% correct? Your not getting near the efficiency from a torque converter which is consistently unlocking itself to multiply torque under load. So your going to get equal or better mileage with an auto when the efficiency is well below the 100% the manual is getting under the same load? I mean, you say it's intentionally designed to allow slippage right? Slippage creates more heat and less efficiency from what the experts over at ATS have to say on the matter;
------------------
Efficiency
Efficiency, according to industry definition, is simply the ratio of the impeller speed to the turbine speed. If the engine is running at 2000 RPM, the impeller is directly connected to the engine so it is also rotating at 2000 RPM. If the turbine were spinning at 1800 RPM, this would be defined as a 90% (1800/2000=90%) efficient torque converter.
Efficiency numbers are very misleading because the number depends on many factors including load, vehicle speed and torque converter design. At one extreme, picture your truck sitting at a stop light with the engine idling at 750 RPM. The impeller is turning at 750 RPM, but the turbine isn´t moving. 750/0=0%. At a stop light the torque converter is zero percent efficient.
A more typical example would be an engine running at 2000 rpm at highway speed and a turbine speed of 1800 rpm resulting in a 90% rating. This is the method that current efficiency ratings are determined. However, this methodology is flawed. An example of the other extreme illustrates this. Imagine a truck going down a big grade with no lockup clutch and using an exhaust brake. The engine will be holding the truck back and the turbine will actually be spinning faster than the impeller. In this case if the engine was at 1800 rpm and the turbine was at 2000 rpm, the efficiency would be 2000/1800=111%. The truth is no mechanical device can be more than 100% efficient, so there is obviously a problem with conventional torque converter efficiency ratings. In addition, we have just illustrated three cases where the same truck is subjected to three different loads, resulting in three different efficiency ratings.
The point is, many manufacturers like to claim high efficiency ratings, but unless each torque converter is compared under the exact same standardized conditions, these efficiency numbers are meaningless. Don´t be fooled by reported efficiency ratings. For all practical purposes these numbers can´t be compared between manufacturers and are simply marketing propaganda.
Torque converter efficiency really is the ability of the stator to "get out of the way" and not impede ATF flow when the impeller and turbine are spinning at approximately the same speed. 100% efficiency can only be achieved when in lockup with no lockup clutch slippage.
------------------
In fact since we've last parted on this subject I've done quite a bit of reading on various torque converters and the like. These guys know what they're talking about - and they all agree the OEM manufacturers produce junk. There are so many ways in which to improve on current OEM automatics to make them more reliable and bullet proof. I'd bet an ATS modified tranny can do eveything a ZF can do except offer the same crawl ratio or potential control for a very certain set of limited circumstances - this comes at a premium cost however, and the Torqueshift is no ATS tranny - not even close. The 4r100 is even further off.
As to low end torque - the manuals don't multiply torque like an auto does - HENCE the reason for that ultra low gear for moving heavy loads - all in all they get just as much torque to the ground - if not much more, due to the fact that the automatic is trading efficiency for torque multiplication and is geared much higher (lower numerically)- period.
Speaking strictly of factory transmissions. Speaking strictly of the two specific OEM transmissions offered in the Ford Super Duty. And speaking only of people who can drive either type very competently - if all these criteria are met, I see more advantage for the manual over the auto. This goes for durability, reliability, ease
of maintenance, and cost efficiency.
I can summise two things from here; 1.) I'm never at a loss for words when provoked.
2.) All of this should get your goad pretty good.
#70
10-15-2005, 05:00 PM
It has always been my opinion that the term "torque multiplier" is grossly misleading. If converters could truly multiply torque then we would have a phenomen the likes of which we haven't seen since cold fusion and having them lock up would be counter productive. What they can do is allow a certain amount of slippage and a few hundred rpm difference from input to output. Under the right conditions this may allow the engine to operate higher on the torque curve and in a good system hopefully some of this increased torque will make it to the output. However, as outlined previously this is simply trading a great deal of efficiency for a small increase in speed.
P.S. I love a good debate but this one my be getting to personal. Happy Trails
P.S. I love a good debate but this one my be getting to personal. Happy Trails
#71
10-15-2005, 05:36 PM
sinister, you must have read my thread about my 2 cents why manuals wont be offered after 2010, (question from fredvon). you elaborated immensely on it. its called the pussification of america. but cut fredvon some slack. he brought up very detailed info on the automatic trannies, and i can say they have come a long way. my V10 has a 5 speed manual and thats what i prefer. i have bought 7 new ford trucks all with manual trannys, and have paid every one of them off. all of them had 150,000 plus on them before i sold them. NEVER put a clutch in any one of them. never a problem with the trannys either. but this topic has been beat to death. it comes down to preference like fredvon said finally. judging by the length of your posts, you have a lot of time. come out in the woods and bang gears like me, use your granny low, ITS FUN! your points are well taken as are fredvon's.
#72
10-15-2005, 06:56 PM
Some of a Lesson I used to teach at the School house in Maryland known as Aberdeen proving Grounds (APG):
Stator --- the stator can be described as the "brain" of the torque converter, although the stator is by no means the sole determiner of converter function and characteristics. The stator, which changes fluid flow between the turbine and pump, is what makes a torque converter a torque converter (multiplier) and not strictly a fluid coupler.
With the stator removed, however, it will retain none of its torque multiplying effect. In order for the stator to function properly the sprag must work as designed: (1) It must hold the stator perfectly still (locked in place) while the converter is still in stall mode (slow relative turbine speed to the impeller pump speed) and (2) allow the stator to spin with the rest of the converter after the turbine speed approaches the pump speed. This allows for more efficient and less restrictive fluid flow.
The sprag is a one-way mechanical clutch mounted on races and fits inside the stator while the inner race splines onto the stator support of the transmission. The torque multiplier effect means that a vehicle equipped with an automatic transmission and torque converter will output more torque to the drive wheels than the engine is actually producing. This occurs while the converter is in its "stall mode" (when the turbine is spinning considerably slower than the pump) and during vehicle acceleration. Torque multiplication rapidly decreases until it reaches a ratio of 1:1 (no torque increase over crankshaft torque.) A typical torque converter will have a torque multiplication ratio in the area of 2.5:1. The main point to remember is that all properly functioning torque converters do indeed multiply torque during initial acceleration. The more drastic the change in fluid path caused by the stator from its "natural" return path, the higher the torque multiplication ratio a given converter will have. Torque multiplication does not occur with a manual transmission clutch and pressure plate; hence the need for heavy flywheels, very high numerical gear ratios, and high launch rpm. A more detailed discussion of torque multiplication can get very confusing to the layman as high multiplication ratios can be easily considered the best choice when in fact more variables must be included in the decision. Remember, the ratio is still a factor of the engine torque in the relevant range of the torque converter stall speed, i.e.: a converter with a multiplication ratio of 2.5:1 that stalls 3000 rpm will produce 500 ft.-lbs. of torque at the instance of full throttle acceleration if its coupled to an engine producing 200 ft.-lbs. of torque at 3000 rpm. However, if this same engine produces 300 ft.-lbs. of torque at 4000 rpm, we would be better off with a converter that stalled 4000 rpm with only a 2.0:1 torque multiplication ratio, i.e.: 300 x 2.0 = 600 ft.-lbs. at initial acceleration. Of course it would be better yet to have a 2.5:1 ratio with the 4000 rpm in this example (provided his combination still allows the suspension to work and the tires don't spin.) This is just a brief overview as the actual scenarios are endless.
And from my lesson plan some simple math demonstrated on a simulator that I don't have a picture of any more:
A torque converter couples two driveline axes, transferring torque and angular motion by the hydrodynamic action of a viscous fluid. Unlike a friction clutch, it cannot lock the axes together. The Torque Converter block models a torque converter acting between the two connector ports I and T as a function of the relative angular velocity of the two connected driveline axes. The input is the connector port into which power flows into the block. The output is the connector port from which power flows out of the block. The I port represents the impeller or pump. The T port represents the turbine. Forward power flow means power flowing from I to T. Reverse power flow means power flowing from T to I. Forward motion means the relative angular velocity ¦Ø = ¦Ø<SUB>T</SUB> ¨C ¦Ø<SUB>I</SUB> > 0.
Because the coupling of the axes occurs by viscous action, the torque transfer depends on this difference ¦Ø. In normal operation, the two axes have different speeds, and the output T axis speed never exactly reaches the input I axis speed (¦Ø < 0). The torque transfer is largest when |¦Ø| is large and shrinks as |¦Ø| shrinks. Because |¦Ø| can never reach zero exactly, a torque converter always transfers some torque.
You specify the torque ratio and the capacity factor of the torque converter as discrete functions of the speed ratio with tabular vector entries. The three vectors of the independent and two dependent variable values must have the same length.
¦Ó<SUB>input</SUB> is the torque flowing into the shaft with the larger speed, and ¦Ó<SUB>output</SUB> is the torque flowing into the shaft with the smaller speed.
Two functions specify the characteristics of the torque converter: the torque ratio R<SUB>¦Ó</SUB> and the capacity factor K, both as functions of the speed ratio R<SUB>¦Ø</SUB>. You specify these as discrete tabulated functions in the dialog.
R<SUB>¦Ó</SUB> = R<SUB>¦Ó</SUB>(R<SUB>¦Ø</SUB>)
K = K(R<SUB>¦Ø</SUB>)
In normal operation (forward power flow), the input impeller (I) and output turbine (T) torques are
¦Ó<SUB>I</SUB> = sgn(1 - ¦Ø<SUB>T</SUB> / ¦Ø<SUB>I</SUB>) ¡¤ [¦Ø<SUB>I</SUB> / K]<SUP>2</SUP>
¦Ó<SUB>T</SUB> = ¦Ó<SUB>I</SUB> ¡¤ R<SUB>¦Ó</SUB>
<SUB></SUB>
I little piece stolen form one of my racing suppliers:
THE TRUTH ABOUT STALL TORQUE RATIO
STR has been talked and argued about for many years. The following information is what we at Precision Industries have found by doing our own testing to be helpful for you to try to understand this subject. Our competitors must have a crystal ball to figure the STR of their torque converters. There are a couple of companies in the performance torque converter business that do have the capability to test STR, MOST DO NOT! Precision Industries happens to be one that does have. Our test dyno has the capability to test from 200 ft. lbs. of torque up to 900 ft. lbs. of torque. The other companies use dynamometers that vary from 100 ft. lb. of torque to approximately 300 ft. lb. of torque. There is an old GM printed sheet that has floated around our industry for about 10 years showing the STR of stock GM torque converters that were built back then. Our competitors either use this sheet or are guessing because they have no way of knowing what the STR really is. They also advertise STR¡¯s of 2.7, 2.9, 3.0, 3.2, etc. this is pure BS. All torque converter companies use the impellers, turbines and stators that come in the factory torque converters. In our tests we have never seen an STR over 2.55. Precision Industries do have torque converters with STR over 2.55 but these units have specially machined stators in them and are not worth the high cost for a street/strip application. If our competitors try to tell you differently just ask them to show you a picture of their test machine, not just a printout. The formula for STR is EXACT OUTPUT TORQUE ¡Â EXACT INPUT TORQUE = STR. This requires a known power source and a data recovery system. STR is just what the name implies. The ratio of torque multiplication at stall. As soon as the turbine rotates (car moves) the ratio starts dropping rapidly until enough RPM has been reached for the ratio to drop to 1:1. The RPM that the ratio reaches 1:1 varies depending on other factors in and out of the torque converter such as impeller exit angle, stator design, impeller to turbine clearance, input torque (engine), etc. A fact that most everyone overlooks is that a torque converter does not make torque! It takes the torque the engine produces and multiplies it for a very short period of time.
I am sorry if some of you want to believe that all the torque Converter does is convert RPM to heat. But gee whiz fellows! It is called a TORQUE CONVERTER for a reason.....sheesh!
Stator --- the stator can be described as the "brain" of the torque converter, although the stator is by no means the sole determiner of converter function and characteristics. The stator, which changes fluid flow between the turbine and pump, is what makes a torque converter a torque converter (multiplier) and not strictly a fluid coupler.
With the stator removed, however, it will retain none of its torque multiplying effect. In order for the stator to function properly the sprag must work as designed: (1) It must hold the stator perfectly still (locked in place) while the converter is still in stall mode (slow relative turbine speed to the impeller pump speed) and (2) allow the stator to spin with the rest of the converter after the turbine speed approaches the pump speed. This allows for more efficient and less restrictive fluid flow.
The sprag is a one-way mechanical clutch mounted on races and fits inside the stator while the inner race splines onto the stator support of the transmission. The torque multiplier effect means that a vehicle equipped with an automatic transmission and torque converter will output more torque to the drive wheels than the engine is actually producing. This occurs while the converter is in its "stall mode" (when the turbine is spinning considerably slower than the pump) and during vehicle acceleration. Torque multiplication rapidly decreases until it reaches a ratio of 1:1 (no torque increase over crankshaft torque.) A typical torque converter will have a torque multiplication ratio in the area of 2.5:1. The main point to remember is that all properly functioning torque converters do indeed multiply torque during initial acceleration. The more drastic the change in fluid path caused by the stator from its "natural" return path, the higher the torque multiplication ratio a given converter will have. Torque multiplication does not occur with a manual transmission clutch and pressure plate; hence the need for heavy flywheels, very high numerical gear ratios, and high launch rpm. A more detailed discussion of torque multiplication can get very confusing to the layman as high multiplication ratios can be easily considered the best choice when in fact more variables must be included in the decision. Remember, the ratio is still a factor of the engine torque in the relevant range of the torque converter stall speed, i.e.: a converter with a multiplication ratio of 2.5:1 that stalls 3000 rpm will produce 500 ft.-lbs. of torque at the instance of full throttle acceleration if its coupled to an engine producing 200 ft.-lbs. of torque at 3000 rpm. However, if this same engine produces 300 ft.-lbs. of torque at 4000 rpm, we would be better off with a converter that stalled 4000 rpm with only a 2.0:1 torque multiplication ratio, i.e.: 300 x 2.0 = 600 ft.-lbs. at initial acceleration. Of course it would be better yet to have a 2.5:1 ratio with the 4000 rpm in this example (provided his combination still allows the suspension to work and the tires don't spin.) This is just a brief overview as the actual scenarios are endless.
And from my lesson plan some simple math demonstrated on a simulator that I don't have a picture of any more:
A torque converter couples two driveline axes, transferring torque and angular motion by the hydrodynamic action of a viscous fluid. Unlike a friction clutch, it cannot lock the axes together. The Torque Converter block models a torque converter acting between the two connector ports I and T as a function of the relative angular velocity of the two connected driveline axes. The input is the connector port into which power flows into the block. The output is the connector port from which power flows out of the block. The I port represents the impeller or pump. The T port represents the turbine. Forward power flow means power flowing from I to T. Reverse power flow means power flowing from T to I. Forward motion means the relative angular velocity ¦Ø = ¦Ø<SUB>T</SUB> ¨C ¦Ø<SUB>I</SUB> > 0.
Because the coupling of the axes occurs by viscous action, the torque transfer depends on this difference ¦Ø. In normal operation, the two axes have different speeds, and the output T axis speed never exactly reaches the input I axis speed (¦Ø < 0). The torque transfer is largest when |¦Ø| is large and shrinks as |¦Ø| shrinks. Because |¦Ø| can never reach zero exactly, a torque converter always transfers some torque.
You specify the torque ratio and the capacity factor of the torque converter as discrete functions of the speed ratio with tabular vector entries. The three vectors of the independent and two dependent variable values must have the same length.
- The speed ratio R<SUB>¦Ø</SUB> is the output angular speed divided by the input angular speed. You specify a range of speed ratio values from 0 up to, but not including, 1.
R<SUB>¦Ø</SUB> = min[¦Ø<SUB>I</SUB>/¦Ø<SUB>T</SUB>, ¦Ø<SUB>T</SUB>/¦Ø<SUB>I</SUB>] - The torque ratio R<SUB>¦Ó</SUB> is the output torque divided by the input torque.
R<SUB>¦Ó</SUB> = ¦Ó<SUB>output</SUB> / ¦Ó<SUB>input</SUB> - The capacity factor K is the input speed divided by the square root of the input torque.
K = max[¦Ø<SUB>I</SUB>, ¦Ø<SUB>T</SUB>] / ¡Ì¦Ó<SUB>input</SUB>
¦Ó<SUB>input</SUB> is the torque flowing into the shaft with the larger speed, and ¦Ó<SUB>output</SUB> is the torque flowing into the shaft with the smaller speed.
Two functions specify the characteristics of the torque converter: the torque ratio R<SUB>¦Ó</SUB> and the capacity factor K, both as functions of the speed ratio R<SUB>¦Ø</SUB>. You specify these as discrete tabulated functions in the dialog.
R<SUB>¦Ó</SUB> = R<SUB>¦Ó</SUB>(R<SUB>¦Ø</SUB>)
K = K(R<SUB>¦Ø</SUB>)
In normal operation (forward power flow), the input impeller (I) and output turbine (T) torques are
¦Ó<SUB>I</SUB> = sgn(1 - ¦Ø<SUB>T</SUB> / ¦Ø<SUB>I</SUB>) ¡¤ [¦Ø<SUB>I</SUB> / K]<SUP>2</SUP>
¦Ó<SUB>T</SUB> = ¦Ó<SUB>I</SUB> ¡¤ R<SUB>¦Ó</SUB>
<SUB></SUB>
I little piece stolen form one of my racing suppliers:
THE TRUTH ABOUT STALL TORQUE RATIO
STR has been talked and argued about for many years. The following information is what we at Precision Industries have found by doing our own testing to be helpful for you to try to understand this subject. Our competitors must have a crystal ball to figure the STR of their torque converters. There are a couple of companies in the performance torque converter business that do have the capability to test STR, MOST DO NOT! Precision Industries happens to be one that does have. Our test dyno has the capability to test from 200 ft. lbs. of torque up to 900 ft. lbs. of torque. The other companies use dynamometers that vary from 100 ft. lb. of torque to approximately 300 ft. lb. of torque. There is an old GM printed sheet that has floated around our industry for about 10 years showing the STR of stock GM torque converters that were built back then. Our competitors either use this sheet or are guessing because they have no way of knowing what the STR really is. They also advertise STR¡¯s of 2.7, 2.9, 3.0, 3.2, etc. this is pure BS. All torque converter companies use the impellers, turbines and stators that come in the factory torque converters. In our tests we have never seen an STR over 2.55. Precision Industries do have torque converters with STR over 2.55 but these units have specially machined stators in them and are not worth the high cost for a street/strip application. If our competitors try to tell you differently just ask them to show you a picture of their test machine, not just a printout. The formula for STR is EXACT OUTPUT TORQUE ¡Â EXACT INPUT TORQUE = STR. This requires a known power source and a data recovery system. STR is just what the name implies. The ratio of torque multiplication at stall. As soon as the turbine rotates (car moves) the ratio starts dropping rapidly until enough RPM has been reached for the ratio to drop to 1:1. The RPM that the ratio reaches 1:1 varies depending on other factors in and out of the torque converter such as impeller exit angle, stator design, impeller to turbine clearance, input torque (engine), etc. A fact that most everyone overlooks is that a torque converter does not make torque! It takes the torque the engine produces and multiplies it for a very short period of time.
I am sorry if some of you want to believe that all the torque Converter does is convert RPM to heat. But gee whiz fellows! It is called a TORQUE CONVERTER for a reason.....sheesh!
