Or know what to look for if I put a pressure gauge in my system to determine how restrictive it is?

 

I was hoping you had a stock 4.8L so I could laugh at you, but since you have a BAMF for an engine I am interested.

 

I know Parish8 did back in the day when he had his whippled Z71. Maybe send him a PM about this thread.

 

Did KB measure his or did he use a formula to determine his flow?

 

i did with the turbo but never with a blower. i taped a 1/8" fitting into the exhaust and ran a couple feet of copper line. then adapted to a presure sensor and loged it.

on a turbo set up anything under a 2-1 presure ratio is pretty good. with a blower i am not sure at all. i would say if you are more than a few psi that you would make more power with better exhaust. i think it depends on your cam more than anything. something with little overlap wont be as effected with some back pressure but something with a lot of overlap hates exhaust back presure.