Dale;
Think of a V-12 as being two inline- 6s arranged in a "vee". The I-6 is
inherently a balanced layout so a V-12 will be as well. Ditto for a
flat-12 like a Ferrari 512.
When you take a balanced inline (straight) 6- cylinder engine and rotate
every other cylinder 60 or 90 degrees, the planes of the cylinder banks
are now out of balance.
No, a V-twin can't be completely balanced. Theoretically, if you had a
horizontally- opposed two- cylinder engine with no offset between
cylinders (forked rods) and fired both cylinders at the same time, it
would be in "balance" but the torque ripple would be equivalent to a
single-cylinder.
Here's some interesting reference material on balancing; it is written
primarily with aircraft (Lycoming?) in mind but I think you will find it
useful:
http://www.prime-mover.org/Engines/GArticles/BALANCE.Lyc
Regards, Neil Tucson, AZ
-----Original Message-----
From: Dale Krumheuer [mailto:dmirror3@yahoo.com]
Sent: Tuesday, October 12, 2004 1:50 PM
To: Albaugh, Neil; Rick Yacoucci; land-speed@Autox.Team.Net
Subject: RE: Crank Balancing ( Math )
Ok Neil, now that you gave me enough information to get me thinking, why
is it that you can completely balance a V12 but not a V6 ? Now, to
reduce the question, can a V-twin be completely balanced ?
Thanks Neil,
Dale Krumheuer
Cleveland Ohio, where its gettin' cool
"Albaugh, Neil" <albaugh_neil@ti.com> wrote:
Rick;
It isn't possible to balance a 4-cylinder engine completely, no
matter
what you do. All you can do is minimize the vibration.
On the other hand, an in-line 6 cylinder engine or a V-12 can be
balanced but a V-6 or V-8 can't be completely balanced. There
are
"rocking couples" that cause vibration in engines that do not
have
symmetry.
Now--- someone explain to me the rationale behind a 10- cylinder
engine.
??????
Regards, Neil Tucson, AZ
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