Ok, I have this 350 Long Block I am about to put into my 1992 Camaro RS, the block is from a guy I know, its only got like 12k miles on it and he told me it produces 305hp and 405tq, he is good to his word, so i can trust him, but i am adding a stock TPI intake to the top of it off a 1987 IROC Z, the car was originally a 305 TBI, so i had to get the wiring harness for it too, but my question is how much horsepower will i gain with the TPI intake and I am putting headers with 3'' exhaust with cat and 40 series flowmaster muffler, that being the only mods I am doing to it right now. And if i add a 58mm throttle body some new runners and fuel injectors along with ignition and intake with the computer chip, how much horspower do u think i will produce, if there is anyone that can help me out, or give me some tips that would be nice, thanks

 

From what I've read on here, I think the 58mm trottle body will be an over kill. I seen many threads that say the stock 48mm is good up to around the mid 300's, maybe a little higher. That being said, I would go with a 52mm if you plan on being around that HP or higher in the futuer.

 

You'll prolly only see topside of 260-265hp with the STOCK TPI.

Don't waste your time w/ the 58mm Throttle body. The TPI is very restrictive. Spend that money on upgraded base/runners.

Port your plenum.

Throw away the 882's

Current injectors are OK.

Gut your airbox (Free!!)

Exhaust is great idea (w/ headers).

And the best free most important idea to give you is...

 

so what if i upgraded runners and throttle body to like a 52mm and then port out the plenum and stuff, i am just looking for horsepower upgrade, so do u think that will help out