Background to the question: I'm getting started with modding my '91 TBI Firebird. So far i've got a whole new exhaust for it consisting of the 1-5/8" primary Hedman Hedders, a hi-flow Catco cat, and the Dynomax 2.5" catback. On the way is the Edelbrock TBI intake manifold, and an open element aircleaner along with the ultimate TBI mods.
My question is, with the proper chip programming, approximately
how much hp with this parts combo do you think will remain
caged up by retaining the stock swirl-port heads and stock cam? Just looking for approximations based on opinions and individual's experiences with their own cars. I haven't touched this car as far as actual mods go, just need a heads up on what to expect with what i'll already have. Thanks for any help and/or advice.

 

stock cam is holding aboyt 25hp without heads from what i hear the heads depending on which you get could be holding back 50ish...

 

if you are gonna keep the 305, might as well throw in an LT1 cam. Will only cost you about $200 (50 cam, 50 new timing chain, 40 new springs, ~60 misc.)