400 HP and Good Towing Capabilities Possible???
#16
03-19-2015, 04:29 AM
Excellent explanation by Pocket, and that warning for a finish is where I must stand and applaud. While getting Stinky dialed in with 400 HP, I bent the driveline and spun the pinion bearing in the rear end because of axle wrap - but my HD4R100 has taken it so far.
#17
03-19-2015, 04:39 AM
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I still find these threads interesting even though we usually end up with the same good advice, but each situation has subtle nuanced differences.
Pocket, thanks for your usual good explanation.
From my perspective it sounds like $10-12K.....lol Which really isn't all that bad.....injectors, turbo, tuning a built transmission/drivetrain from TC to Rear End in addition to the usual mods of intake (without it what good is a bigger turbo), exhaust, regulated return, gauges etc.
And then, if I'm reading this correctly, someone might have a rig capable of maintaining a heavy tow putting 400hp to the rear wheels with a reduced risk of something breaking........reduced vs. eliminated. :-)
Am I reading that right?
Pocket, thanks for your usual good explanation.
From my perspective it sounds like $10-12K.....lol Which really isn't all that bad.....injectors, turbo, tuning a built transmission/drivetrain from TC to Rear End in addition to the usual mods of intake (without it what good is a bigger turbo), exhaust, regulated return, gauges etc.
And then, if I'm reading this correctly, someone might have a rig capable of maintaining a heavy tow putting 400hp to the rear wheels with a reduced risk of something breaking........reduced vs. eliminated. :-)
Am I reading that right?
#18
03-19-2015, 05:09 AM
Close.... You would have a truck capable of up to 400 HP for the dyno, but towing would still stay in the 300-350 HP range. Our engine does not lend itself to 400 HP sustained under load without ubermodifications to keep it cool.
The transmission alone was $4K installed, and shiny new AC 160/100s are about $2600-$2800 if my memory cells are rubbing two sticks together. AIS can't do 400 HP, but S&B can. A good turbo that fits the collector, or a T4 mod and a more common turbo - either option is about the same price. 4" turbo-back exhaust, plus resonator for drone. Billet intake plenums (because there is little hope the stock plenums will hold it together), CAC boots, better spider clamps, Hutch mod, Riffraff OCR, gauges (dial and OBDII), ladder bars... it's the trinkets that sneak up on your wallet.
All of that is assuming the truck is 100% to start with.
The transmission alone was $4K installed, and shiny new AC 160/100s are about $2600-$2800 if my memory cells are rubbing two sticks together. AIS can't do 400 HP, but S&B can. A good turbo that fits the collector, or a T4 mod and a more common turbo - either option is about the same price. 4" turbo-back exhaust, plus resonator for drone. Billet intake plenums (because there is little hope the stock plenums will hold it together), CAC boots, better spider clamps, Hutch mod, Riffraff OCR, gauges (dial and OBDII), ladder bars... it's the trinkets that sneak up on your wallet.
All of that is assuming the truck is 100% to start with.
#19
03-19-2015, 07:37 AM
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My understanding is 350-400rwhp towing is about tops for what our drivelines can handle consistently and it is not out of the realm of possibility to keep things cool at those levels depending on how much time you want to spend on tuning. It still comes down to choosing the right injector, turbo and tuning to accomplish the goals you set out.
350hp with manageable EGTs makes for a very nice towing platform.
I don't tow heavy enough to even need that much, only 7000-8500lbs, plus payload in the bed.
350hp with manageable EGTs makes for a very nice towing platform.
I don't tow heavy enough to even need that much, only 7000-8500lbs, plus payload in the bed.
#20
03-19-2015, 07:55 AM
Either way you look at it 400 rwhp is going to be expensive!! But much cheaper than buying another vehicle. I have absolutely no issues with the truck in my signature towing, that would be " the other truck", it's built to tow while stupid power was a side affect 
the cost to get a truck to hold together and be reliable is ASTRONOMICAL. I've said it before that a 300-400 horsepower vehicle is more fun to drive every day then one with even more power.
Is 400 horsepower a number you just picked out of the blue or have you driven one with 350-400 hp? If someone in your area has a truck with slightly more or less power then you're thinking you want ask them to take you for a ride or drive. Then you'd have a better understanding of what it feels like... I don't want to come off rude or anything if I did I apologize I don't know your background.
the cost to get a truck to hold together and be reliable is ASTRONOMICAL. I've said it before that a 300-400 horsepower vehicle is more fun to drive every day then one with even more power.Is 400 horsepower a number you just picked out of the blue or have you driven one with 350-400 hp? If someone in your area has a truck with slightly more or less power then you're thinking you want ask them to take you for a ride or drive. Then you'd have a better understanding of what it feels like... I don't want to come off rude or anything if I did I apologize I don't know your background.
#21
03-19-2015, 08:06 AM
I've taken the power level on Stinky as far as I would ever care to. Ripping the tires and getting sideways on the interstate when I went to pass a pokie doing 40 MPH got me to thinking "what would I do with more than this?" Spinning tires at 400 HP works out to the same acceleration as doing it with 500 HP - but I can understand those that grunt and puff their chest out with 500 HP in 4X4 and a foot buried in the testostopedal. It's just not for me - the 400 HP cost enough.
#22
03-19-2015, 08:29 AM
John, My outlook is that it is still cheaper to fix/play with this truck than it is to purchase another one. I have rode in a 400hp truck. Loved it and kinda got addicted to the power once I drove it. My end goal is to have a truck to play with in the 375 to 400 hp range from time to time but to have a solid towing vehicle when its time for the camper.
#23
03-19-2015, 09:23 AM
#25
03-19-2015, 09:45 AM
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#28
03-19-2015, 02:50 PM
Can you make power and still tow? The answer is a combination of parts and tuning, and what you are willing to trade/sacrifice to make it work. The short is yes it can be done, the long......
Turbo selection is pretty standardized on these engines, so that's easy. Same with exhaust, intake, intercooler, and various other mods. The main component is fueling, and controlling it with proper tuning.
The first thing you need to look at: injectors. The HEUI injector delivers up to a fixed amount of fuel per injection event. There are many components and variants here, but to make "useable" power your ultimate goal is to deliver a greater amount a fuel in a shorter amount of time per shot, and do it while still maintaining adequate injection pressure to get atomization.
So how do you simultaneously increase fuel delivery AND shorten pulse width?
The easy part is picking an injector size in CC's that can deliver the amount of fuel required. The hard part is picking a nozzle size to deliver the fuel in the time you need, and then tuning it to deliver precisely that amount and at the right time.
Smaller nozzles are easier to tune and easier to maintain "street manners". Go with too small of a nozzle when trying to increase power, and the pulse width must be increased dramatically to deliver enough fuel to reach that power. The wide pulse width results in heavy smoke output, and increases EGT's as more fuel is delivered and as RPM's climb. This means that power output cannot be sustained and fueling must be cut in order to prevent skyrocketing EGT's.
Larger nozzles are often much harder to tune, and require a lot of adjustments and tweaking in order to deliver equal or near equal "street manners" of smaller nozzles. However, larger nozzles can deliver a greater amount of fuel in a much shorter amount of time, resulting in (if tuned correctly) very little smoke and greatly reduced EGT's compared to equal power output of smaller nozzles.
Go with too large of nozzles and it becomes almost impossible to maintain "street manners", and intensive professional tuning is absolutely required. At the same time atomization can suffer and it can be difficult to control a minimum pulse width, to the point that smoke output can easily increase. This makes it impractical for most towing applications.
In the end you need the correct matching injector size to run the power you are trying to sustain, which will usually be an injector that can achieve a much greater peak power output.
By the way..... the problem towing with 400+ hp on tap isn't the motor, it's the drivetrain that likes to break. You have been warned......
Turbo selection is pretty standardized on these engines, so that's easy. Same with exhaust, intake, intercooler, and various other mods. The main component is fueling, and controlling it with proper tuning.
The first thing you need to look at: injectors. The HEUI injector delivers up to a fixed amount of fuel per injection event. There are many components and variants here, but to make "useable" power your ultimate goal is to deliver a greater amount a fuel in a shorter amount of time per shot, and do it while still maintaining adequate injection pressure to get atomization.
So how do you simultaneously increase fuel delivery AND shorten pulse width?
The easy part is picking an injector size in CC's that can deliver the amount of fuel required. The hard part is picking a nozzle size to deliver the fuel in the time you need, and then tuning it to deliver precisely that amount and at the right time.
Smaller nozzles are easier to tune and easier to maintain "street manners". Go with too small of a nozzle when trying to increase power, and the pulse width must be increased dramatically to deliver enough fuel to reach that power. The wide pulse width results in heavy smoke output, and increases EGT's as more fuel is delivered and as RPM's climb. This means that power output cannot be sustained and fueling must be cut in order to prevent skyrocketing EGT's.
Larger nozzles are often much harder to tune, and require a lot of adjustments and tweaking in order to deliver equal or near equal "street manners" of smaller nozzles. However, larger nozzles can deliver a greater amount of fuel in a much shorter amount of time, resulting in (if tuned correctly) very little smoke and greatly reduced EGT's compared to equal power output of smaller nozzles.
Go with too large of nozzles and it becomes almost impossible to maintain "street manners", and intensive professional tuning is absolutely required. At the same time atomization can suffer and it can be difficult to control a minimum pulse width, to the point that smoke output can easily increase. This makes it impractical for most towing applications.
In the end you need the correct matching injector size to run the power you are trying to sustain, which will usually be an injector that can achieve a much greater peak power output.
By the way..... the problem towing with 400+ hp on tap isn't the motor, it's the drivetrain that likes to break. You have been warned......
My understanding is 350-400rwhp towing is about tops for what our drivelines can handle consistently and it is not out of the realm of possibility to keep things cool at those levels depending on how much time you want to spend on tuning. It still comes down to choosing the right injector, turbo and tuning to accomplish the goals you set out.
350hp with manageable EGTs makes for a very nice towing platform.
I don't tow heavy enough to even need that much, only 7000-8500lbs, plus payload in the bed.
350hp with manageable EGTs makes for a very nice towing platform.
I don't tow heavy enough to even need that much, only 7000-8500lbs, plus payload in the bed.
Pocket pretty much covered it.
The only caviat I bring up is where the towing is being done... Pulling in the mountains is a completely different ballgame than pulling flatland (IMO anywhere else out of the mountains). If you are only pulling 9000 lbs behind you, even with a payload, I can see the need for 400HP on the pedal. Why burn the motor down and driveline when its not really needed. I'm not saying you don't need the hp, but why pull at that power setting, why not turn it back a few notches? Sure 400+ hp is fun to hot rod with once and a while. Shoot the new rigs are yanking around a 25,000+ trailer on less than 400 hp to the wheels, why 400 for 9000 :-)
We did a quite few trips this year from CO weighing pretty darn close to 25,000lbs in a standard cab OBS 350. Did about 11,800 miles in total with that load. Trailer weighs 9k empty.
That being said, is there really a reason for towing at a sustained power level? The only time I want that much grunt is when I'm hauling that weight in the mountains of CO, and to be honest I'm more concerned with stopping whats behind me once I get to the top, not so much getting it up the hill. 90% of the time i was in a bone stock tune on a set of 160s singles, not until we got back to CO/MT/WY did we need to bump it up.
I know 4:10s and a manual will make a bit of a difference towing over an auto and 3.73s, but even on my measly turd in a stock tune she did just fine. Also, I ran near 200 degrees cooler at the head driving across WI compared to CO. Is it bad I have wanted a set of 3.73s for some time now.
Anyone know if a ZF can even take 400hp reliably for a heavy climb say over an hour or so?(I 70) I hope it can, might try it out some time.
#29
03-19-2015, 03:18 PM
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#30
03-19-2015, 03:21 PM
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Well put! Where are you located in CO?
Pocket covered pretty much covered it.
The only caviat I bring up is where the towing is being done... Pulling in the mountains is a completely different ballgame than pulling flatland (IMO anywhere else out of the mountains). If you are only pulling 9000 lbs behind you, even with a payload, I can see the need for 400HP on the pedal. Why burn the motor down and driveline when its not really needed. I'm not saying you don't need the hp, but why pull at that power setting, why not turn it back a few notches? Sure 400+ hp is fun to hot rod with once and a while. Shoot the new rigs are yanking around a 25,000+ trailer on less than 400 hp to the wheels, why 400 for 9000 :-)
We did a quite few trips this year from CO weighing pretty darn close to 25,000lbs in a standard cab OBS 350. Did about 11,800 miles in total with that load. Trailer weighs 9k empty.
That being said, is there really a reason for towing at a sustained power level? The only time I want that much grunt is when I'm hauling that weight in the mountains of CO, and to be honest I'm more concerned with stopping whats behind me once I get to the top, not so much getting it up the hill. 90% of the time i was in a bone stock tune on a set of 160s singles, not until we got back to CO/MT/WY did we need to bump it up.
I know 4:10s and a manual will make a bit of a difference towing over an auto and 3.73s, but even on my measly turd in a stock tune she did just fine. Also, I ran near 200 degrees cooler at the head driving across WI compared to CO. Is it bad I have wanted a set of 3.73s for some time now.
Anyone know if a ZF can even take 400hp reliably for a heavy climb say over an hour or so?(I 70) I hope it can, might try it out some time.
Pocket covered pretty much covered it.
The only caviat I bring up is where the towing is being done... Pulling in the mountains is a completely different ballgame than pulling flatland (IMO anywhere else out of the mountains). If you are only pulling 9000 lbs behind you, even with a payload, I can see the need for 400HP on the pedal. Why burn the motor down and driveline when its not really needed. I'm not saying you don't need the hp, but why pull at that power setting, why not turn it back a few notches? Sure 400+ hp is fun to hot rod with once and a while. Shoot the new rigs are yanking around a 25,000+ trailer on less than 400 hp to the wheels, why 400 for 9000 :-)
We did a quite few trips this year from CO weighing pretty darn close to 25,000lbs in a standard cab OBS 350. Did about 11,800 miles in total with that load. Trailer weighs 9k empty.
That being said, is there really a reason for towing at a sustained power level? The only time I want that much grunt is when I'm hauling that weight in the mountains of CO, and to be honest I'm more concerned with stopping whats behind me once I get to the top, not so much getting it up the hill. 90% of the time i was in a bone stock tune on a set of 160s singles, not until we got back to CO/MT/WY did we need to bump it up.
I know 4:10s and a manual will make a bit of a difference towing over an auto and 3.73s, but even on my measly turd in a stock tune she did just fine. Also, I ran near 200 degrees cooler at the head driving across WI compared to CO. Is it bad I have wanted a set of 3.73s for some time now.
Anyone know if a ZF can even take 400hp reliably for a heavy climb say over an hour or so?(I 70) I hope it can, might try it out some time.
Trust me, I personally don't have eyes on 400hp, I have too many other things to do other than chase down issues caused by a need for more power.....lol
And yes, towing at altitude is way different.......at least from what I hear.....we have reasonably steep grades to pull in the northeast but they aren't "at altitude".....so a hill with plenty of O2 left is way different than the same hill with thin O2.....