transamice

Does anyone know what size the runners and intake come in an 87 Trans Am GTA, Im thinking of getting a 52mm throttle body and I heard the intake manifold stock handles 52mm but Im not sure about the runners, any feedback plz...

D's89IROCZ

You 'might not even needa 52 mm TB . The stocker flows pretty good. The whole intake itself is a restriction. a 52 mm TB won't do much on a stock setup . What is your setup ?

Daz

iTrader: (1)

You can also mod the stock TB to make it into a 52mm from 48mm.Any carb shop could do it as well

transamice

So far I have a stock setup with cold air intake, was thinking maby larger runners or even Holley stealth ram intake with 52 mm TB.
Engine is stock, headers coming soon and chip.
Just doing bolt on stuff for now.

Cruz'N Bruz'R

The HSR will do it. But there's no point bolting a larger TB onto the stock intake and runners. Save your money and buy an HSR setup, then put the larger TB on.

transamice

Whats an HSR setup?

Cruz'N Bruz'R

Holley Stealth Ram

transamice

How about the 52mm TB with SLP runners on a corvette manilfold, would that help at all to make a difference for the better?

Cruz'N Bruz'R

I'm not TPI guru by any means. I hate the sh*t and went to carb, the only way to make "real" power.

But really, for the price of an HSR, and the fact that it definately works, you can't go wrong. And I wouldn't bother mixing production crap, even off the vette, with aftermarket, because it's probably not much different then what came with your car to begin with.

For $299 from Summit, you can have the whole HSR manifold + runners(one piece) and plenum. Then I think it's another $175 for the fuel rail kit which comes with a regulator, and then you have about the best going TPI setup on the market today.

6speedIROC

iTrader: (3)

As gar as I know all TPI parts are pretty much equal. ie the Vette stuff is no better than 305 stuff when it comes to airflow.
I'd also recommend the HSR unless you can get the runners and TB used for a good price. You could also look at an LT1 intake conversion, it is somewhat similar to the HSR. LT1 intakes can be had pretty cheap. I think Kevin Vandevene had one for sale?
LT1 guys run the stock 48mm TB up to around 400HP if that tells you anything.
At least get one of those TB flow smoothers that go between the TB blades, those work.

transamice

By getting the HSR setup though it shows that you need aftermarket aluminum heads to match it up with, correct me if Im wrong.
Just reading which applications it needs, it mentions it specifically with 5.7L engines, I dont see why it wouldnt work with cast iron.
Im problem reading it wrong.
Im debating between going carb or just staying injection, very few tell me to go carb, most say injection is alot better.

transamice

Emissions is stopping me for now till next year, but Im sure I have better potential with injected system for balancing power and gas milage.
So far its been good for a 5.7L

Cruz'N Bruz'R

Actual, with the way gas is nowadays, it would probably be best to stay with EFI. And I think the whole HSR and aluminum head is crap. It'll work on anything.

transamice

For a good injected setup what would you recommend though.
I was thinking 52mm TB, SLP runners, hi-flow manifold, ported plenum.
Thats as much as I would go if thats what would make a diff.
Is it worth it or not just for simple bolt ons.

Cruz'N Bruz'R

I don't know. I looked at how much it would cost to make the power I wanted to make with EFI, and I got rid of it.
The stock TPI really sucks. My beer barrel EFI setup on my R/T pulls better, with less cam, than my 5 speed TPI ever did. But going to a larger TB would be the last thing I'd do before upgrading all of the rest of the intake tract.

Think of how much the SLP runners are gonna cost, and the high flow manifold. Then the time you'll invest in porting the plenum...
...then hope it works.

If money was tight I'd port everything yourself without spending any money, and see if that helps at all, but probably not much.

But for the price, the HSR is a proven system that works. Alot of fast cars are running it. It looks easy to work on, unlike that damn SuperRam, and it doesn't seem to be that expensive. At least not compared to the price of bigger intake and runner setups when I was looking when I was still TPI.

Remember, you can still sell your stock setup stuff after as well. You should be able to get $50-$100 back for your stock intake stuff.

Buddy

[QUOTE=Cruz'N Bruz'R]I don't know. I looked at how much it would cost to make the power I wanted to make with EFI, and I got rid of it.
The stock TPI really sucks. My beer barrel EFI setup on my R/T pulls better, with less cam, than my 5 speed TPI ever did. But going to a larger TB would be the last thing I'd do before upgrading all of the rest of the intake tract.


I don't think I would say that really. Your Iroc stock should ROAST an R/T. The TPI intakes ARE torque biased. It's proven. For a street car, where you see mostly street RPM's (below 4500) the TPI makes more power than some of the aftermarket intakes. You have to decide where this car will live most of it's life RPM wise before you decide which intake to buy - if any.

Here, check this out in the classifieds.

https://www.thirdgen.org/forums/part...e-intakes.html

Cruz'N Bruz'R

My LB9 was a dog, even with the 5 speed. My R/T recently ran a 15.2@91mph with a horrible 2.43 60ft on a Beltronic. I know my LB9 wouldn't have broken 15s in a long shot. All i know is that as ****ty a design as the stock mopar intake is, it's still makes more power and more torque than the TPI does stock, with less cam, way less cam. Albeit, it's 12 yrs newer in design than the TPI. All I'm saying is if your seriously in the hunt for power, keeping the stock TPI stuff on there is like jamming a golf ball in a vacuum cleaner and wondering why it doesn't suck.

Hawk92z-TDZ

Something was really wrong with your LB9 then, mine ran 14.8 stock, well it did have a K&N

Cruz'N Bruz'R

I'm sure it did.