Hello,
I am new here to the forum. I have recently acquired a '91 GTA that has an '87 350 TPI. The motor has a Lunati cam in it, has been bored .030 over, has headers on it and a single split exhaust (not a true duel ). I am also running a 700R4 automatic transmission. Anyways, I have two main questions.

1. Does anyone have a guess to what my hp and torque are from this motor? I am just wondering since I haven't had it dynoed yet.

2. I want to put a turbo/supercharger on it, but only have about $800 to spend. I have been told that, since it is high compression, i should probably just stick with a supercharger. I am open to rebuilt chargers and i am not looking to beat everything, just something to make me competitive on the street without breaking the bank. Any ideas?

Thanks,
Brandon

 

bump

 

Brandon, your budget is very low, so I would stick with a naturally aspirated engine for now. Go heads and cam, matched with the right injectors, intake and tune. Quite a few guys here have been deep into the elevens with their L98's that way, while staying totally streetable.

 

Thanks Street Lethal. Do you or anyone have a good setup in mind that I could run? I would like to know specifics on parts if I could get them. Or does anyone know of anyone who could sell me a good set up? Thanks.

 

$800 sounds like a perfect budget for a 150-175hp nitrous kit and an ignition upgrade.

 

x2...

800 will get you ALOT when it comes to nitrous.

 

how many lbs of boost could i get with $800 including the cost of a mechanic to put it all in?

 

none.

you are wasting your time.

the blower alone will likely cost more.

 

im in the process of buying a turbo setup and my injectors fuel pump and megasquirt to tune cost more than 800 alone thats not including turbo intercooler piping manifold etc

 

i have over 800 in my stealthram conversion alone with all the fittings/fuel system.

 

The stock 87 tpi makes 230 hp/330 ft lbs at the crank. Add in a proper cam, with some headers, .030 bore and possible compression increase depending on the pistons selected.. stir lightly and add 93 octane. The big unknown here is the cam. If it was carefully selected to match the torque producing nature of the tpi setup, you are in good shape. If they went for a loping higher rpm/horsepower cam, you might be in worse shape than stock. A trip down the track would be $20 well spent to find out what you're producing. My guess is somewhere between 270 to 310 crank hp. It's doubtful they chose a torque based cam that could have put you closer to 400 ft lbs of torque but you never know.

Your biggest enemy is lack of funding, closely followed by the unknown compression. It's even possible you have the same or less compression than stock.

Anyway, assuming you're making 300 hp, figure that for every 15 psi of boost you'll make another 300hp. So half of that, 7.5 psi should give you around 150 hp extra. There are factors and variables that make the real number lower than that, but it's a useful guide.

Ok, so a blower or turbo to produce 7.5 psi will cost you north of $1000 and that's if you really shop around and find a good deal on a used blower or an ultra-budget home made turbo setup. Add to that improved spark and some kind of fuel management (FMU to stay on a budget) and I'd say the very least you'll come out of this with some boost is $1500 to $2000.

You can pick up a tpi nitrous system 100-150 hp for under $600 brand new and about half that used. Yes you have to fill up the bottle, but just consider that payments. It's like putting a $800 down payment on a turbo system and making payments from now on.. except you don't have to do any of the hard work to get it. This is coming from a former nitrous addict. I always drove around with a spare full nitrous bottle back in the day!

 

i think i am leaning more towards the nitrous right now. I really like the fact that I will be able to set up the system to use the nitrous only at WOT. Where can i get the tpi nitrous setup for less than $600 tho? The only tpi setup i saw was $650. Also, where could i get a used setup? That would be awesome to save more money.

 

Here is the original information I was given from the guy who sold the car to me. I can get specifics in a few days when I get my car back from the shop (the documents are with the car at the shop)
* less than 4,000 miles on the motor !!!!
* 350 Bored 30 over
* Life is 489 intake & 489 Exhaust
* Forged Flat top pistons
* From oil pan to intake...all new
* New A/C delco fule pump
* Lunati Cam & Filters
* Duration 50% is 215 intake4279 exaust 279
* NEW Edlebrock Headers
* New Flow Master Muff w/3"exhaust
* New rear end w/alumi. T/A Rear Cover w/345 gears 4 wheel disc brakes.
* New...High Performance Transmit. 700R4 w/NEW BM torque converter w/2400 Stall

 

that sounds about right.