How do you determine CFM when it comes to HP potential?

[Mighty Thor]

This is sort of hard to do isn't it. The BD-11a model of Powerdyne air flow is rated at 900 cfm. I think that's pretty good. It beats some of Paxton and Vortech's head unit.

But how do you convert that into HP and in relation to our car's HP?

Is there a formula for this?

[Turbo V6 Camaro]

CFM has alot of factors

CUbic inches rpm and VE are the mjor one's

VE is the big one cause a car having 85% VE vs a car with 40% sucking the same amount of air... well that just means car #2 is wasting it and not making the most out of what it has...

thats the basic i know i have never really looked into really deap..... but mor air + more fuel = power

and trwoing FI on the car is a hole different story cause you can have VE of over 100%

[Mighty Thor]

I never quite understand that myself. Alot of SC and Turbo are basing their HP gain from the CFM they could get from their blower. But yeah, I know what you mean about VE.

[AlienInv8r]

I've read that you can use mass flow rate to get a general idea of how much power you are making. CFM is a volumetric flow rate unit; generally mass flow rate is given in lbs/min. You can convert your CFM to lbs/min using the ideal gas law (PV=nRT ). If you multiply your lbs/min by 10 it gives you a very general BHP approximation (ie - 44 lbs/min =~440bhp). Like Viper said, it will depend on the VE of the engine, other mods, intake temperature, etc, but that can give you a general approximation as to what kind of power your putting out.