Find me one modern domestic V8 (gas or diesel) that has a balance shaft. None do. The only V engines I know with balance shafts are V4s , V6s (sometimes) and V10s (sometimes). Even then that is not fighting against gravity, its counteracting the natural motion of the pistons/crankweights.
Flex has nothing to do with torsion. Torsion is twisting, that is what you get with a long piece of metal with force being applied in a rotary motion. Like an inline engine crankshaft. Flex is an entirely different thing.
Because that is just how it is, there is nothing that inherently makes an I6 better then an I8, V8, V16 or V12 other then that it makes for easy maintenance and easy in-frame overhauls.

 

i didnt realize you were the man making the decisions my bad. weres your proof for that statement?

flex has everything to do with torsion. and just because something is longer doesnt mean it will "twist". because you know the cranks are only a 1/4 inch thick and made of plastic in a incline motor!


i noticed you only want me to list a v8. i wonder why? well i do know the ford V10 has one

 

really? what is that force of nature that gives something weight?


ok, ill try to explain this a simple as i can. i v engines pistons lay at a angle. what the angle is i dont know. since each piston is at an angle gravity is pulling down on its side into the sleeve or chamber causing friction. it is a very small amount but it is there. the motor has to overcome this force.

 

There's this thing called inertia. It's a product of MASS not WEIGHT. Any frictional losses due to gravity on a V-style engine would also be present on an inline engine. Instead of the weight of the pistons laying partially on the cylinder bore it would be on the wrist pins. Either way you still have a very small amount of friction. [/QUOTE]

 

That is true but the way a incline runs the cylinders are are the exact opposite of each other, counteracting eachother perfectly. Its not constantly fighting itself. a inline is going straight up and down being perfectly balanced. piston #1 balances #6, #2 balances #5, and #3 balances #4, largely eliminating the polar rocking motion that would otherwise result. Secondary imbalance is avoided because an inline six cylinder crankshaft has six crank throws arranged in three planes offset at 120°. The result is that differences in piston speed at any given point in rotation are effectively canceled.


i guess you could think of it as a teater totter that is perfectly balanced. its is very easy to move the side up in the air to the bottom. with very little force. so basically the effects of gravity are being counter balanced. same with an incline.

 

i wonder what the gearing will be in the rear end? prob 8.93's

 

Its easy enough to see the logic. An I6 offers no other advantage
Torsional forces are always there, no matter what. Flex is physical bending of the crankshaft back and forth. That is where more main bearings comes into play. Torsional is physical twisting - the longer the crankshaft the heavier it needs to be to withstand torsional vibrations. Why do you think most engines have that honking huge harmonic balancer up front? Its helping to cancel out harmful torsional vibrations.
The same reason you keep listing an I6. I2, I3, I4s, I5, I7, etc.. all need balance shafts in order to be smooth running. They will run without them, but will often vibrate A LOT. You see this with larger and older 4 cylinder engines without balance shafts.

The Ford V10 has a balance shaft, yes. The Dodge v10 on the other hand doesn't.
Its possible to have a V engine be like that too - See V12s and V16s.
Mass is not the same as weight. Gravity has nothing to do with engine balance. You can take an unbalanced single cylinder engine upto into space, and it will shake around just as much up there as it does down here on earth.

The friction from being at a 45* angle is negligible. Its the side load (the crankshaft/conrod wanting to slam the piston against the side of the wall) that matters more. This would be even more pronounced with a long stroke engine.

 

yes there are a few foreign cars with i4's that require a balance shaft but there are no I6's, I5's, and I7's that i know of that use a balance shaft. the I2's and I3's were primaraly in motorcycles and i have no clue about those.

the whole point of bwm and other luxury cars using incline motors is that there is very little to no vibration.



im well aware of the difference between mass and weight. never did i say that gravity makes a v10 or a v8 or an v style motor unbalanced. all i said is that a V motor has to fight gravity.


not debating you but the fact is that gravity still is a acting force as well. may not matter to you but its there. if you took that motor into space then it would not have the same side pressure. maybe not enough to measure but there would be a difference.

 

The incline doesn't really have anything to do with that.

It has to do with the INTAKE system taking up enough room that the head has to be moved to one side.

Why?

BALANCE of the entire engine, otherwise it would have to be offset to one side so the car doesn't sit funny. That, and room for the intake side of things. Without a V and funky intake runners running around in circles, the intake runners have to be a certain length for the intended engine RPM range. The only way to do that with any sanity is to incline the cylinders.

--

Interesting aspect of the V10: Four-bolt mains, AND crossbolts, for a total of 6 bolts holding each main bearing cap.

 

I don't think the effect of gravity is really going to matter. Your claiming gravity will increase friction, which will be minimized by the engine oil anyway. Yes, technically it's there, but you're talking 0.01% of the engine performance or some tiny minute amount of it.

I understand that engines with more cylinders per a bank will run smoother (specifically if they have 6 cylinders per bank - i.e. I6 or V12), they will also be easier to work on, but other than that I don't think there is any real advantage to them other than space issues.

Take for instance my I4 in my Saab, it's a noisy little bouncy engine compared to my V10 at idle. I betting Saab put alot more engineering into refining their engine than Ford did.

 

There's much more acceleration ("G"s) of the pistons and rods going back and forth, or up and down, compared to the one "G" of Earth's gravity.

 

Exactly what I was tiring to say.

 

And still, no real discussion of Ford's plans for the V10:

FORD CLASS-EXCLUSIVE V10 GAS ENGINE, TORQSHIFT TRANSMISSION WILL POWER MEDIUM-DUTY CHASSIS CABS | Ford Motor Company Newsroom

Funny...

 

I guess the truth hurts sometimes.

I would like to have the new 6 speed in my truck though, would be nice even if I would only use 6th gear about 10% of time. I know I would get better mpg for that 10%.

 

6th gear is the same as your 5th.