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Air Flow......................................>>>

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First I lets make an assumption of 100% volumetric efficiency. This just means that all 600cc are filled when the piston reaches BDC of the intake stroke. On a 4-stroke the intake stroke only happens every other stoke or at half the rpm (1000rpm = 500 intake stokes). Now for some conversions.

1cc = .00003531 cf (cubic feet)

* 600 = .021186 cf

cfm = (.021186)*(rpm/2)

10.59cfm @ 1000rpm

21.19cfm @ 2000rpm

31.79cfm @ 3000rpm

42.37cfm @ 4000rpm

52.97cfm @ 5000rpm

63.56cfm @ 6000rpm

74.15cfm @ 7000rpm

84.74cfm @ 8000rpm

95.34cfm @ 9000rpm

105.93cfm @ 10000rpm

A 10.59 increase change in cfm per 1000 rpm. On a naturally aspirated engine VE is dependent on many factors and the above scale would not be a constant increase. In actual use the above engine might only have 50% VE @ 10000rpm (300cc of combustable mixture). This is where cams, valve size, porting, intake and exhaust systems, etc. come into play.

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WOW . Thanks You shure do know alot about Engines , and I am very happy for your input . a VERY BIG THANK YOU !!!


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