<style type="text/css">p { margin-bottom: 0.08in; }</style> Your ideas are fascinating but perhaps not easy for full scale implementation. Lets say that you have e.g. 7 or 8 or 9 non-symmetrical cylinders. When you need full power/torque it will be difficult to minimize vibrations and perhaps other ill effects.

 

A Super Duty weighs a good 1000-2000 lbs more than an equivalent OBS truck and has much much stricter emissions standards to adhere to.

Yes, it does have two plugs per cylinder. Big bore engines, especially with the pseudo-hemi head design like the 6.2 (and the Chrysler 5.7/6.1/6.4 Hemi) have a harder time controlling combustion and emissions. They could either use a bigger/more restrictive cat, or use two plugs per cylinder.

As far as valves go, I doubt really a 4 Valve head will be made any time soon. GM and Chrysler have both proven that 2 valve heads can flow more than enough air. The main requirement to make a 2 Valve head work though is big valves - which require a big bore. The old 4.6 and 5.4 modular engines simply didn't have a big enough bore to allow for big enough valves.

 

Yeah, that's gonna be one rough running engine. Time for another American standby, the balance shaft! Invented in England, patented to Japan now, and used in cases where a shoddy engine design needs to be smoothed out so it will seem to run like a properly designed one!
Regards, Eric

 

this is here to fill the 10 character minimum..
essentially to say thanks for the info with a simple.

 

Huh? Any inline 3,4 or 5 Cylinder engine will need balance shafts in order to be smooth. It is not physically possible to cancel out the vibrations in those engine types without balance shafts. Certain V-Angle V10 and V6 engines also need balance shafts to cancel out unwanted vibrations.

 

That's all true. Don't forget the 60 degree Duratec based V8 that also needs one too.

I was talking about that non-symmetrical cylinder engine that the other fellows were talking about. I'm thinking maybe they can rig up a balance shaft that will smooth out this crazy engine that would have uneven firing pulses because the bigger cylinders are producing more power than the smaller cylinders are, and also to smooth out the imbalance brought about as the result of the bigger cylinders having bigger, heavier pistons than the smaller cylinders do. The other route of giving some cylinders longer strokes than the others would also bring about imbalance issues, again necessitating the need for some kind of external balancing help from a balance shaft. I honestly don't think it could be made to work though.

In other words, what I am trying to say in a round about way is I don't think this non-symmetrical cylinder engine is very practical.
Regards, Eric

 

Yes it would be more expensive but since trucks cost more than a house already why not shoot for the moon?

Yes there is also parasitic loss but at speed it isn't very much. Right now it is possible to make a V8 run on only two cylinders dragging the others along. But the loss is minuet compared to the gain of not feeding those cylinders with fuel. But what would be really neat and even more expensive is if you could uncouple the "extra" cylinders from the rest of the motor which would mean no friction loss. But that is even more far fetched of happening than a variable CI motor. Also ALL 4 cycle engines have parasitic loss wasted on the exhaust stroke. It is a small amount of loss but it is a loss after all. This loss can be seen in the differences between a 4 cycle engine and a 2 cycle engine. I think you said fords new 6.2 V8 engine puts out something like 332hp. In the 2 cycle world it only takes 100 pounds and 3 cylinders to bypass that. PSI builds big bore kits for polaris snowmobiles that are just insane both in HP numbers and price. Take a look at this little 360HP 3 cylinder: PSI Engines
Now just imagine someone was able to valve a 2 cycle or fire a 4 cycle every revolution to eliminate the wastefull exhaust stroke.

Most of that minus the gas guzzling monster V8 can be found in old hondas. When I say old I mean as far back as the late 80's early 90's. PSD's are another story. We will see how fords new diesel will hold up over time. Not so much a production motor but if you want to talk technology advanced big V motors just look at F1 cars. Who powers all the F1 cars? It sure isn't fords stone age V8's.

YouTube - Honda F1 motor test

Also remember fords failed attempt with the hybrid ranger/explorer that was a strait up hurry up and get it out there copy of hondas insight and toyotas prius. They just did it with a compact truck chassis to try and be different.


This can be looked at two ways. One saying yes efficiency is being hindered by the quest for more hp but at the same time hp is a byproduct of efficiency. In fords quest for big hp numbers to try and keep up with the other guys efficiency comes after hitting goal hp numbers. If gas mileage was the number 1 goal you wouldn't see the hp numbers you are seeing, they would be much lower.

My kids are up now and I can't think with all the noise any more. I believe I am starting to ramble on so I'll quit for now. These are great healthy conversations here! I love it!

 

Each cylinder/piston rod combo would be balanced to its own flyweights on the crank. The only thing that could cause a shake is the "missing" of cylinders when they are shutoff. However this could be taken care of with some careful planning of which cylinders are fired when. Remember it doesn't have to be the same 2, 3, 4, etc cylinders fired all the time. The computer can control random firing of random cylinders when need be to smooth out the miss fired cylinders.

 

Because the 6.2L is the base engine. It's designed to make the trucks affordable!

This is true, but if I remember right 2-stroke engines are far less efficient than a comparable 4-stroke engine. Much more power per unit of displacement, as there are twice the number of power strokes, but the design in general is very inefficient.

Sure, but who does make a high-tech truck motor? The Toyota Tundra? Other than 4V heads, what does the Tundra have that the new 6.2L doesn't?


[QUOTE=SnowseekerThis can be looked at two ways. One saying yes efficiency is being hindered by the quest for more hp but at the same time hp is a byproduct of efficiency. In fords quest for big hp numbers to try and keep up with the other guys efficiency comes after hitting goal hp numbers. If gas mileage was the number 1 goal you wouldn't see the hp numbers you are seeing, they would be much lower. [/QUOTE]

In this day and age fuel economy IS the priority. Look at the new 2012 Focus: Same 2.0L engine, but with direct injection and a healthy horsepower increase from 130 to 160 horsepower! EPA numbers not released yet, but I'm pretty confident there's a healthy increase.

I agree with you, I love getting into good debates here on FTE. Often folks take it personal and I have to stop early, thanks for keeping it fun!

 

It doesn't work like that. You can't think of an engine as a bunch of single cylinder engines - you have to think of it as a whole. You would have a crankshaft with a bunch of different size counterweights swinging around. It would be a huge vibrational mess. It is not possible to balance out all the vibrations of a specific cylinder with just counter weights.

Look at engines such as the Boxer 6, or the Inline 6. They have perfect primary and secondary balance without the use of balance shafts. This is because the way the counter weights are placed along the crankshaft, they cancel each other out. This is just not possible with the engine design you are proposing.

I'm also not sure what an F1 engine has to do about anything. You do know that Honda isn't the sole supplier of F1 engines? Ford-Cosworth even had some offerings at one point. You do also know that F1 engines are not allowed to use VVT/VCT, variable intake runners, etc...F1 engines are very low-tech compared to modern automotive engines. The only thing worth noting really in an F1 engine is the metallurgy and the valve train.

As far as Honda having all the technology the 6.2 does back in the 80s/90s - also not true. Honda had V-TEC since '89, which only switched between two camshaft profiles. They didn't add variable valve timing to the mix until 2001.

 

If 50-60K is considered affordable. What is the price tag of a stripped down XL F250 2011 now anyhow? The only prices I know of are the ones I see here which are fully or near fully loaded trucks with all the bells and whistles.



That is correct that 2 strokes aren't very efficient but they do make great power. What would be great though is making a 4 stroke fire every stroke to eliminate the drag and parasitic loss of the exhaust stroke. I believe this could be done using both the 4 stroke and 2 stroke design. Using the 2 stroke exhaust cylinder ports and using the 4 stroke intake valves in the head. Intake force would be needed to charge the cylinders via a supercharger or turbo. The 2 cycle blow threw waste would be eliminated with the use of the 4 cycle intake valve system. The now used direct fuel injection would also cut down on the 2 cycle waste. Like anything though once built and tested it can be improved upon once flaws are found. I feel if an engine can fire every stroke the size of the engine can be reduced but still producing the same if not more hp which in turn should produce better efficiency not only from the engine itself but also from saving weight.



Not so much a real truck but hondas ridgeline has a "high tech" motor. Coincidentally the same motor that is in my honda odyssey mini van. Funny story. Last year the wife and I were on the way back from a night out. I pulled up to a sto light that was red. This intersection is on a one way road, from the light the road goes from 3 lanes down to 1 within 1/8ish mile. To my right a guy with a convertable BMW pulls up with the top down. A guy in his 50's with his (what looked like to me) high maintenance wife sitting in the passanger seat. As we were waiting for the light to change I could tell he wanted to get out ahead of me before the single lane by the way he was inching forward and watching the opposing traffic light. Well the light turned green and I left the light like I normally would. I noticed the BMW left a little hard and was on a mission. So being a guy I floored the little 3.5 vtec mini van and the tires let out a slight screech. The BMW's back bumper was even with my front bumper at this time. To my amazement and my wifes fright we were slowly pulling on the BMW! When we got to the single lane my front bumper was even with the BMW's drivers door. The other driver had to let off and fall in behind me on the single lane road. At the next stop sign two blocks up the road I took a right hand turn and watched my rear view mirror. As the BMW driver went strait I could see he flipped me off. His wife looked as though she was smilling. I would have loved to hear the conversation that followed in that car. I couldn't believe the BMW didn't have it over the measly mini van. I LOLed.

2006 Honda Ridgeline Long-Term Road Test | Vehicle Reviews Blog & Discussions at Truck Trend Magazine



To me honestly that is kind of sad. The B16A vtec motor (1.6L) in my 1989 honda civic puts out 170hp and gets 35mpg religiously. The new 2011 honda civic 2.0L dohc vtec engine puts down 197hp. All while getting equal or better gas mileage of the competitors. I know it sounds like I am biased toward honda but I kind of am. How can you argue with more hp, better mpg's, and better reliability?



Every now and then I take stuff personally. I try real hard not to and have to tell myself to calm down some times but every now and then it gets out. I have gotten much better at not letting things bother me as much as they used to. I have learned that no matter what I say some people will not change their thoughts on some matters. Even when I know I am right I have learned it is best to just stay quiet and not get involved with some discussions/arguments. I am always up for a good intelligent conversation about mechanics though! I love this stuff! Hope this is still fun for all.

 

The 2011 F250 XL starts at $28,335. Slightly higher than the previous gen, but this one comes standard with the 6-speed auto.

I believe it! Just bought my wife a 2011 Toyota Sienna, and that thing can MOVE. It's AWD though, and seems to average 20 MPGs in the cold up here. I'm new to Wisconsin, and I think the lousy fuel economy is due to the nasty weather. My 400 HP truck gets 18 BTW...


But what are you comparing it to? Your expensive, high-feature 4-cylinder is the premium engine option for each of those cars. And they aren't cheap.

The 2012 Focus is an economy commuter car, and this engine is the base option for the car. Compare that to the Civic's 140-HP base engine and I think it's pretty impressive.

The 2012 Focus ST will have an EcoBoost 2.0L engine making nearly 250 HP!

That's exactly right, I learned long ago that it's very tough to change people's opinions. But a well-intentioned debate normally involves learning on both sides.

 

I guess that isn't so bad.



Yes the colder snowy weather does take a slight toll on mileage. The cold air takes more fuel to compensate, you end up idling vehicles more to keep them warm, but mainly the cold air/fuel compensation is what eats up mileage the most.




We will see what that new focus gets for mileage. Everything always sounds good when the maker talks about it but when it hits the streets the real story comes out. We will see what honda has for 2012 as well. There are rumors but those are almost always wrong.

As far as the ecoboost motor I would say it is average. It is easy to make hp numbers with a turbo. Honda does it NA which I find way more impressive. 100hp+ per liter NA is amazing. But if the rumors are true that might change as well.




Normally.

 

It is possible, have you ever worked with a piston pump? Essentially a motor of a certain size driving another motor/pump of a different size without excessive vibration. The only way to fine tune an engine is to think of every cylinder as an individual engine.

If you take three different sized balanced motors and hooked them together you would have a single balanced motor.

Balance shafts are a bandaid. They are not needed if proper research, testing, and tuning are implicated. This very thing can be seen between mitsubishis I4 2.0L used in older eclipses, lasers, and talons and now used in evolutions which all use balance shafts to try and smooth out the outdated technology cast iron motor. Now honda with the same basic I4 has NO balance shafts and runs just as smooth if not smoother than the mitsu motor. Why does one use balance shafts and not the other? Wierd isn't it.

Because only the best are chosen to build F1 engines.


There is/was more to gain from the variable cam lift, duration, and timing (yes vtec does all three) than the simple degreeing of the cam(s). The new honda motors do it all with multiple stage cam control. Pioneers that others try to imitate. Ford, chevy, and dodge all stick their money into marketing, honda sticks their money into research and development.

 

Yes, I am familiar with piston pumps, but I'm not sure what you're getting at
This is correct, but there are primary, and secondary vibrations. Counter weights only cancel out the primary vibrations directly related the the piston/rod going up and down. The counter weight swinging around induces its own vibrations side to side. In Straight 6, Flat 4/6 and V12 engines, the counterweights are positioned in such a way that the side to side rocking motion the counterweights generate perfectly cancel out. This can only happen because the counterweights are all the same weight, and are positioned a specific way. Your idea of different cylinders with different sizes cannot work, because it is not possible to have a perfectly balanced single cylinder engines without balance shafts.
Balance shafts are not a bandaid, it is not physically possible to make an Inline 4 cylinder engine with perfect primary and secondary balance. Many Honda engines have balance shafts as well. The H, F and even the K24 in the Civic you used as an example earlier all have balance shafts. Smaller 4 cylinder engines, like <1.6L can get away without balance shafts because of the smaller masses being swung around.
Yeah, I guess that is why my '02 Honda CRF450 dirtbike needs to have the piston replaced every 100 Hours (around 50 hours if racing) to prevent the skirt from collapsing and the piston flipping in the bore. I guess that is also why even if you ride it easily, you will have to replace the crankshaft every 300 hours or so to prevent potential rod breakage or bearing seizure. I suppose that is why I have to check the valve clearance every 15 hours of run time because the intake valves on these bikes have a nasty habit of sinking into the head - even if ridden easily.

Honda is far from the best - and my dirtbike that is in pieces right now for a piston replacement is proof of that.
V-TEC is just on/off (some engines did have 3 stage). You have two different camshaft profiles. iVTEC added continuously variable valve timing in '01. Honda did not pioneer variable valve timing either. The first engines to use variable valve timing showed up in the 1920s. Porsche was the first to apply it to a car, and Alfa Romeo also used in the 1980s. Ford started using variable cam timing a full 3 years ahead of Honda...