That's like trying to guess what someone runs the mile in without knowing their age, weight and physical status level.

That answer can be anywhere from 40 to 100hp...so without knowing specifics we can't answer squat.

 

if your asking the basics ls1 heads flow around 235 cfm stock vs ls6 260-265 stock (ruff #'s but you get the point) ported depending on stage you can get around 290-300 cfm flow ls1's vs upto around 330 ls6. my TSP stage 1 heads flow 307. hope that helps cheers! for the money i'd look at TSP stage 2.5 heads. just my one cent.

 

Ok cool thanks alot guys you all been tons of help. Ill be back with more questions im sure.