Not Ranked
Big is not always better. Here is some info from an HP "Auto math" book I occasionally find interesting. First the formulas...
Air capacity =(rpm*displacement)/2
1728 is cubic inches in a cubic foot
CFM= (rpm*displacement)/(2*1728)
3456=2*1728
so...
Theoretical cfm= (RPM*Displacement)/3456
Volumetric efficiency= (Actual cfm/theoretical cfm)*100
standard engine cfm= ((rpm*displacement)/3456)*.85
Performance engine cfm= ((rpm*displacement)/3456)*1.1
A performance example from the book... Using a 650 cfm holley a 350 comaro turned a 1/4 mile in 14.35 at 96.05. only change was to a 800 cfm Holley now it runs 14.61 at 95.44. Book recommends run the formulas. If they fall between sizes go with the smaller one. May not be cool or help bragging rights, but it may be a better performer.
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