So how much hp will it support? Im gona run this on my b18a and im shootin for 350whp w/forged internals, and some skank2 springs and some delta regrinds. I think tha the turbo will rock on this set up, quick spool time and all, but its not gona be a dyno queen. It should pull like a mother ---- in the crx.

here is the TO4 40 at 17psi and 8k
Im moving about 490 cfm on this map



here same setup but at 7k
about 428 cfm at

 

As a gross generalization, it takes a bout 150 Feet3 to make 100 HP @70 degrees. (Not taking into account thermal inefficiencies) You are going to run signifficantly hotter charge-air into your engine the closer you get to the choke line. depending on your setup, I peg it at about low 320's. Best "guess".