List of automotive superlatives

[bone]

^10 is an even number as well

it's because you have 4 cycles in a combustion engine, and if you have 4 - 8 or 12 cylinders, you have each time 1 - 2 or 3 cylinders combusting at the same time

where by a V10, you have one cycle 3 cylinders combusting, the next cycle, only 2 cylinders combusting at the same time

so in theory, a V10 makes no sense

 

[thedguy]

^10 is an even number as well

it's because you have 4 cycles in a combustion engine, and if you have 4 - 8 or 12 cylinders, you have each time 1 - 2 or 3 cylinders combusting at the same time

where by a V10, you have one cycle 3 cylinders combusting, the next cycle, only 2 cylinders combusting at the same time

so in theory, a V10 makes no sense

That makes no sense.

V10's have a natural imbalance from end to end. The engine has to have an even amount of cylinders inline to have that balance, or fit balance shafts.

If you look at any engine with an even number of cylinder inline, (v/8/12/16 or an Inline-4/6/8 ) They always have a cylinder that will cancel out the movement of another. In an inline 3, 5, or V6/10 you can't do that. V6's were avoided for so long because they were extremely hard to balance, where an I-6 has a perfect balance.

The same reasons a V10 took so long to develop is probably a reason we won't be seeing a V14, other than to have an oddball engine design... so expect the Germans to have one out in the next decade

 

[mmap]

^10 is an even number as well

it's because you have 4 cycles in a combustion engine, and if you have 4 - 8 or 12 cylinders, you have each time 1 - 2 or 3 cylinders combusting at the same time

where by a V10, you have one cycle 3 cylinders combusting, the next cycle, only 2 cylinders combusting at the same time

so in theory, a V10 makes no sense

That makes no sense.

..The engine has to have an even amount of cylinders inline to have that balance...

If you look at any engine with an even number of cylinder inline, (v/8/12/16 or an Inline-4/6/8 ) They always have a cylinder that will cancel out the movement of another.

Now I am one of the most "engineering challenged" persons i know but Bone's explanation makes perfect sence to me and your arguments do not disprove them in any way...

Why does an even amount of cylinders balance each other out?? Could it be that their "cycle" is the same, as Bone was explaining?

 

[thedguy]

Wasn't ment to disprove what he said, I just can't quite figure out what he was saying You'll find out in a moment I'm just as horrible at understanding a verbal explaination as I am at giving one. (I like pictures).

They balance each other out mostly due to firing order. If you look at a 4 cylinder engine, the 2 outer cylinders are always in the same position, and likewise for the 2 inner cylinders, each cylinder is still on a different part of the 4 stroke cycle though.

Since the force of the piston pushing down on the front of the engine has a near equal amount of force on the very back, it causes the vibration to be mostly cancelled out.

Basically both ends of the engine are trying to push down on the motor mounts, on a v10/I5 you'll have 1 end pushing down on the motor mounts, and the other end pushing up, amplifying the Power pulses, rather than dampening them.

Best example I can think of is a teeter todder, a V10/I5 will rock from end to end (1 cylinder pushes one side down, while the other side up). On an I-4 the cylinders on the end are trying to push the engine down, the center pistons are trying to push the motor up, balancing it out (though there are other vibration forces at work).

I'm horrible at explaining things so hopefully that helps.

http://en.wikipedia.org/wiki/V10_engine

 

[bone]

i understand what you're saying, and you're right as well

you're trying to explain that if one cylinder in the front of the engine combusts, there should be another one at the outer end combusting at the same time to minimize vibration

correct, and that doesn't change anything to the things i've said.
i'll try to rephrase my explanation

you have 4 cycles, and 10 cylinders, so cylinder 1, 5, and 9 will be in the situation
2, 6 and 10 will be
cylinders 3 and 7 will be
and cylinders 4 and 8 will be in the same situation

here's a very simple cycle diagram of a 12 cylinder engine (inline to make diagram easy), the x is where it combusts, and the bold are the cylinders when you have to delete to end up with a 10 cylinder engine
x000x000x000
0x000x000x00
00x000x000x0
000x000x000x

as you can see there are 2 lines with 3 x's (not in bold), and 2 lines with only 2 x's (not in bold), so both situations will give different torque readings

now it's probably true like thedguy said, that it won't be cylinders 1 and 5 firing at the same time, but cylinders 1 and 10, to counter the force, but that doesn't change anything to the fact that one time 3 cylinders combust, the next time only 2

so those 3 cylinders smart or opel corsa engines make even less sense, they have a cycle where no cylinder at all combusts

 

[thedguy]

Even worse is a V-twin motorcycle engine like on Harley's and Indian's (I think ducati uses them as well).

 

[un-dee]

It's not that simple

http://www.e31.net/engines_e.html for all who would like some more information on that - easy to understand

 

[mmap]

...I'm just as horrible at understanding a verbal explaination as I am at giving one. (I like pictures).

I am SOOOO with you there!

 

[bone]

have been reading most links posted here, but still don't understand what a balance shaft is :?

if i understand correctly, it's a shaft down in the engine, driven by the flywheel, turning at 4 times engine speeds? and that should cancel out vibration? never heard of it, and never seen it in a stripped engine

 

[thedguy]

They are nothing more than a shaft with weight on one end of it. They look a little like cams.

Balance shafts are designed different for each engine.

On 4 cylinder engines, they are usually only needed when the motor is above 2.0 litres. They spin at twice the speed of the crank.

Many companies are putting them on V6's to balance them out. I believe they spin at the speed of the crank, and sit in the valley between the 2 banks.

They also have to be located in specific places to work. On a 4 cylinder I think it's near the middle of the block (height wise). One needs to be placed on each side of the block.

On a 5 cylinder engine they only need one, and they spin at engine speed and sit just below the head if I recall correctly.

V8's don't need them. Cross plane v8's like the German's and us Yanks make only need counter balancing via a pully or offset weight in the flywheel.

I-6's and v12' have a natural balance and don't require balance shafts. I've heard conflicting information that says Boxer/Flat/Horrizontially opposed engines are perfectly balanced regardless of cylinder count. Since you've always got a piston to offset the movement of another.

 

[bone]

^10 is an even number as well

it's because you have 4 cycles in a combustion engine, and if you have 4 - 8 or 12 cylinders, you have each time 1 - 2 or 3 cylinders combusting at the same time

where by a V10, you have one cycle 3 cylinders combusting, the next cycle, only 2 cylinders combusting at the same time

so in theory, a V10 makes no sense

That makes no sense.

you're right

not all cranks have them under 90?, in theory you could have 1 combustion every 36? of rotation, with none overlapping