Saw on a website how to caclulate VE if you know the peak horsepower and RPM. My motor on a dyno made 400HP at 5500 RPM. So that's

(400*792001.6)/(29.92*10.75*396*5500)=.45
Where 29.92 is pressure (for arguments sake)
10.75 is compression
396 is cubic inches
5500 is RPM at peak HP

Then I calculate theoretical CFM
396*5500/3464 = 628 CFM

Then I calculate Actual CFM
(396*5500*.45)/3464 = 283 CFM

So if I read this right, my engine only needs 283 CFM of air to make 400 horsepower at 5500 RPM?

What is the normal VE of an EFI small block. I feel as though I should be making more like 480HP at 5500 RPM.

What gives?

 

VEs can run from the 80s to 150s.
Unless you doing the measuring during the test your just guessing and the numbers may or maynot make sense.

If you asking about air consumption, you can make 1 HP/1.3 CFM of air.

Just trust the stop watch, and tune to what the engine wants