ok i have an 89 firebird with a 305tbi and 700r4. current mods are wider and stickier tires, 2.5 dynomax cat-back, gutted cat, soon to be hooker 2055's with a y pipe. what else am i going to need yes i know tuning but whats the cheapest way for me to be able to beat an 87 IROC with a L98 motor in perfect running condition and a good driver and it is completely stock.

 

Nitrous.

 

i really dont want to hook up a wet shot of nitrous with the whole needing a second fuel line thing. anything else?

 

try this thread itll get you in the right direction

https://www.thirdgen.org/forums/tbi/...-tbi-mods.html

 

weight reduction and a 3 or 3 1/2 inch catback with the headers.and of course chip work.

 

3" exhaust with headers, then TBI work, manifold, LT1 or ZZ4 cam, chip tune, then heads then another chip tune, then another, another, another, another, then when you think you've got it just right for your set up 5more. Thats the one part of TBI I hate is having to get computers involved...

 

whats wrong with my 2.5" catback from dynomax? is it really going to restrict that much more power than a 3?

 

Yes, especially if you start changing parts in the motor such as cam, heads, intake, etc...

To keep up you are going should have full 3" exhaust, Headers, Intake, Cam swap and lots of tuning. Your exhaust will allow full potential performance of other parts.

Your starting with 170HP & 255TQ. You are trying to compete with 245HP & 345TQ. All of those changes should get you close to those numbers. If you want more you need to change your heads and do more serious tuning. By that time it may be cheaper to start with a 350.

 

I will put it this way, a STOCK truck 4.3 TBI uses a single 3" exhaust.

 

fast i just read your tbi post with the power that your 305tbi makes is crazy gives me hope that i soon can be somewhere about even if not that.