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      05-05-2013, 03:53 PM   #49
CanAutM3
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Quote:
Originally Posted by Boss330 View Post
Really interesting discussion. Some useful info on engine design:

Chapter on torque:
http://www.epi-eng.com/piston_engine...on_engines.htm

Torque charts for a few engine designs:









Thanks for sharing these graphs

The graph for the one cylinder engine reflects well the half revolution (from 360 to 540 degrees) power stroke and then the negative torque required for the compression cycle. There is also a small dip in the torque to push the exhaust gases out and then torque remains slightly negative to suck the charge in.

It is also interresting to see that on the 6 cylinder engine, even if the power strokes overlap, it is not sufficient to overcome the torque consumed by the compression strokes (still some negative torque). Only as of the V8 does the instantenuous torque always remain above zero.

Last edited by CanAutM3; 05-05-2013 at 04:02 PM.