Larry et al: You have to keep the question to cars, and AFAIK, 16 cylinders
has been the practical limit. Besides complexity and weight, there are too
many parts to break, too many pieces to keep together with the correct
clearances, and too much "windige" or frictional losses. A big factor in
the increased weight comes from making the thing stiff enough not to
self-destruct.
You are correct - a V8 is about the best compromise for
parts/power/smoothness. A V6 comes close, but needs a balance shaft to be
as smooth. Now an in-line 6 is very smooth, but that comes at the cost of
longer and heavier. For simplicity and reliability, its hard to beat a
4-banger, but then smoothness goes out the window.
But when you go beyond automobiles, then all bets are off - ALCO (American
Locomotive) makes a dandy V18 that is used on a lot of RR engines, and the
Coast Guard put 2 of them in their "Famous Class" WMEC270 Cutters. Seemed
to be reliable and smooth. About 1500 HP each....
Werner
----- Original Message -----
From: "LarryT" <[EMAIL PROTECTED]>
To: "Mercedes Discussion List" <mercedes@okiebenz.com>
Sent: Friday, December 22, 2006 2:43 PM
Subject: Re: [MBZ] 16 cylinders?
Andrew asked:<< is there any engineering limit on the no. of cylinders>>
I'm just guessing here -- based on things I've read - but I think the
limit
may have to do with the crankshaft flexing - the flat 12 Porsche used in
the
917s of the early 70s had a seperate shaft that transmitted power from the
center of the crank - so the power was coming from the center and not the
end of the crank so the crank did not distort.
I need to read about the design of the 917 engine some more but that's
what
I recall --
I don't recall any engines with more than 16 cylinders -
Larry T (67 MGB, 74 911, 78 240D, 91 300D)
