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SeventyOne · 03-09-2012, 03:18 PM

Well like I just simplified the equation posted above, I am sure the 3456 is some formulation of air volumetrics, x Pi x the moons gravitational pull, etc, simplified down to a simple number...being 3456.

I have also seen the equation with an additional step...multiplying by a coefficient of efficiency. Most carbs/setups being only 85% efficient so you would then multiply the 615.xx cfm by .85 to give you a closer number.

Racing setups or blown applications might raise the coefficient to 1.1. 615.xx cfm x 1.1.

But it won't REALLY matter. just leave that step out and you're in the ballpark. It's not like someone actually makes a carb that fits your equation number EXACTLY...I mean can you go out and buy a 522.xx cfm or 676.xx carb?

03-09-2012, 03:18 PM	#11
SeventyOne Registered User Join Date: Mar 2007 Location: Oakland, Ca Posts: 1,381	Re: Is a 750 carb too big for a 327? Well like I just simplified the equation posted above, I am sure the 3456 is some formulation of air volumetrics, x Pi x the moons gravitational pull, etc, simplified down to a simple number...being 3456. I have also seen the equation with an additional step...multiplying by a coefficient of efficiency. Most carbs/setups being only 85% efficient so you would then multiply the 615.xx cfm by .85 to give you a closer number. Racing setups or blown applications might raise the coefficient to 1.1. 615.xx cfm x 1.1. But it won't REALLY matter. just leave that step out and you're in the ballpark. It's not like someone actually makes a carb that fits your equation number EXACTLY...I mean can you go out and buy a 522.xx cfm or 676.xx carb?