I am new to the forums and I just bout a 89 firebird 5spd v62.8l I was wondering how much hp boost i would get if i installed this http://www.summitracing.com/parts/HY...n/?prefilter=1
also installing headers on the 2.8l would it make a difference?

 

buying a bad of potatochips is a better deal.

 

headers will definitely make a difference. just make sure to get a high flow cat or you might burn it up.

 

Ditto on no to the chip, if I recall all they do is change when the fans come on and some other little thing that doesn't do much of anything. The headers should be a 5-8hp gain, 5 or so with stock exhaust probably, if you couple it with a mandrel bent 2.5" catback and high flow cat, probably 8-12hp gain total.