Simple dumbass question...no searching turns up anything about any car ever using a V-14. Why? There are V-6s, 8, 10, 12, and 16...why do you not see a 14 cylinder?

8/19/2008 12:21:27 PM

I don't think two banks of 7 cylinders would be good vibration wise.

8/19/2008 12:28:39 PM

Why?

8/19/2008 12:29:30 PM

resonant frequencies...someone else chime in

although honda has a GP bike with a V-5

8/19/2008 12:31:43 PM

What about 7 per side makes it unique? I assume it's more than just being an odd number...a V-10 would have 5 per side?

8/19/2008 12:34:03 PM

without thinking too deeply into it, I feel like 5 cylinders per bank can be dampened easily enough with balance shafts. 7 would be more difficult. Plus, the only real perk/pimp factor/luxury of more cylinders is to have a smoother engine, and having to deal with the naturally unbalanced engine is just more of a bother than its worth.

8/19/2008 12:40:08 PM

Why don't you divide 360 degrees by 7 or 14 and see what you get?

All other combinations currently manufactured easily divide 360 into an integer...so my guess is that the design is just that much easier to bring to fruition and keep balanced.

Something interesting to note: how many V12 or V16 engines do you see being currently produced that have ONE common crankshaft? And before you start...the Bugatti Veyron and Volks Phaeton fall into a different category altogether. The only ones I know of are diesels...and they all run at very low rpms (usually below 2000, and most quite a bit lower). Harmonics become a problem if rpms head higher, and shit starts breaking. Remember the breaking crankshaft issue in M3's a couple of years back, when rpms started going over 8 grand?

BTW...a V14 is an entirely possible (and plausible) configuration...but that little math obstacle just makes it a little more daunting. My guess is that its vibration characteristics would be quite favorable, as the firing frequency per revolution (7) would not directly correlate with the 4-stroke cycle. One thing that makes straight sixes so smooth.

[Edited on August 19, 2008 at 12:45 PM. Reason : blah]

8/19/2008 12:40:38 PM

Guessing because no one actually makes an inline 7?

8/19/2008 12:41:17 PM

aston, ferrari, mercedes and all do single crank v12s

8/19/2008 1:16:17 PM

VW had a 2.3L VR5 in europe..

[Edited on August 19, 2008 at 1:20 PM. Reason : not relatd to the orig. post but relavent to the discussion, i guess..]

8/19/2008 1:20:05 PM

v12 has almost no vibration

the 60° v-12 is actually the smoothest type

[Edited on August 19, 2008 at 1:20 PM. Reason : 

8/19/2008 1:20:25 PM

Quote :

"Plus, the only real perk/pimp factor/luxury of more cylinders is to have a smoother engine, and having to deal with the naturally unbalanced engine is just more of a bother than its worth."

not true. more cylinders to get the same amount of displacement allows for a much shorter stroke (assuming a similar bore size). shorter stroke allows for a much happier revving engine.

8/19/2008 1:31:47 PM

Pros:
Shorter stroke, lower piston velocities, smaller bores (which usually means more even combustion chamber temps and less chance of pre-ignition), more main bearings which means better crank support,

Cons:
A SHIT TON MORE FRICTION.
weight,
physical engine dimensions (length)
$$ (more pistons more machining more rods etc.)

8/19/2008 1:40:27 PM

A w32 would be badass. oh hell yeah.

8/19/2008 2:05:33 PM

Quote :

"not true. more cylinders to get the same amount of displacement allows for a much shorter stroke (assuming a similar bore size). shorter stroke allows for a much happier revving engine."

Good call.

8/19/2008 2:13:59 PM

Quote :

"aston, ferrari, mercedes and all do single crank v12s"

True enough. But they ain't big v12's. They are also heinously expensive...and a lot of time and money has gone into building them well.

a 60 deg V12 is about as smooth as it gets. But it's still got a long crankshaft. And twice as many power pulses per revolution to set induce resonant vibration within a long crank. The longer the crank, the lower the natural frequency. And twice as many pulses. Hmmm. I'm wondering just how a lot of these engines are designed to compensate for first-order harmonics...and hell, there's no doubt that some of them spin fast enough to result in second-order resonance as well.

8/19/2008 4:04:22 PM

they all resonate my balls in hot womens mouths.

8/19/2008 6:22:17 PM

i see what you did there

8/19/2008 6:28:53 PM

^^gg

[Edited on August 19, 2008 at 8:18 PM. Reason : ]

8/19/2008 8:18:31 PM