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Old 05-16-2011, 06:30 PM   #47 (permalink)
TheEnemy
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Quote:
Originally Posted by Old Tele man View Post
...see Fig. 10-7, on page 247, of "The INTERNAL-COMBUSTION ENGINE, 2ed., 1961, International Textbook Company, by Professors C.F.Taylor and E.S.Taylor of MIT:

Fig. 10-7. Volumetric efficiency vs. mean piston speed and Z of the MIT geometrically similar engines under similar operating conditions.

...it's a graph showing that Vol. Eff. "peaks" at piston speeds between 1000 and 1500 fpm, which corresponds to Mach index air-flow Z numbers of 0.3-0.4-0.5.

...Z number is tied into both piston speed and valve size (ie: trying to suck/push air past/though changing valve areas), which gets into Mach index (Z) and maximum air speeds...but, piston speed 'starts' every thing.
Wouldn't that also depend on factors such as your intake runners, cam and such and what those parts flow best at?
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