I have a 89 Iroc tpi 350 and other than removing the smog stuff and the cats and replacing all exhaust except headers it is stock. We are pulling it an building it, but is my goal of 450hp and 500 ft/lbs of torque to much for a weekend driver? I am wanting to keep the tpi. So let's hear it?



**More images of the car and our 87 c10 at http://s1189.photobucket.com/albums/...%20and%20Iroc/

 

450/500 with tpi is going to be tough, you will need new base, runners, port the plenum, bigger throttle body, custom tune. I have seen it done tho so its not impossible.

btw nice car just got mine painted white as well.

 

I have an 85 TPI. I am building an engine spec'd to be at 520bhp. It is possible, just expensive. I am not using the stock manifold. I am going with a holley stealth ram. My block is a 350 bored .060" over and decked to 9.005" I am getting a rotating assembly with a 3.75" stroke.

Your heads will either need to be aftermarket, or ported to all heck with valvework done as well. Im going aftermarket, brand new.

You will also need a pretty hefty cam.

Dont forget, you will also have to make sure the rest of the car can handle all that. Tranny, rear diff, suspension, brakes etc.

And by the way, you got a nice ride man. Good luck with it all!

 

I was really hoping to hit my goal w/o nitrous, but it seems my car wouldn't be very streetable. So is aiming for 350-75hp and 400 ft/lbs or torque with a 150 shot a more realistic way to go? Is the nitrous a bad thing? I don't know much about it, but I don't think I'd want a dry shot. Right?

 

Simple wet kit properly tuned with timing pulled out and a step colder spark plug will be very safe. Nitrous gets a bad rep since alot of people do it wrong

450/500 is more in the lines of a stroker TPI build, 383 to 406 with good ported aftermarket base/runners.

You can siamese the SLP style runners if you can find them and cam it up with good heads to make 450hp on a 355 inch motor, but you will lose the torque. Keep it long tube runner on a 383 and it will get into the 430-450hp range possibly but definately make 500lbft

 

With a well worked TPI 350 its possible to get up into the mid 400s (this is at the flywheel not the rear wheels). There are many articles and builds online describing how they came about accomplishing this very thing. You will need new runners the base will need to be ported heads and cam will need to be replaced ect but essentially these are things you would do with any sbc. Chose your parts carefully and a street able mid 400 hp 350 is very possible.