Well, I finally got my '95 GT a PTK street kit with a T-67. Engine is completely stock (except for pulleys), and I added 42# injectors with matching MAF, Walbro 255lph in-tank pump, and an MSD Digital-6 Plus Ignition with matching wires and coil. The car has a T-56 and 3.73 gears plus an almost full Griggs suspension (sans rear coil-overs).

Anyway, I got it tuned at a very respected local shop and asked them to do so for safety, being that the highest octane gas I can get at my hometown is 90 and the altitude is 7,000 ft. The result is 340 rwhp / 420 lb./ft torque with 8# of boost, which is a little less than I expected (I was aiming for 400)

My questions are:
-what do you guys think of these numbers? Are they too low?
-Keeping the "safety" focus (don't want to blow my engine to hell due to fuel issues), what mods would give me the best bang for the buck in order to achieve my 400 rwhp goal?

Hope you guys chime in with your comments/suggestions soon.

_g.

 

Heads would probably pick you up a barrel of HP! Should easily reach 400+ with a decent set of heads (AFR 165/185's?) and some more tuning.

 

Assuming the car is 'tuned' with just timing and fuel pressure (no add on tuning device), do you have any info on where those are set to, and more importantly, what the A/F ratio was at during those pulls?

I'm sure you can meet your goals with any number of methods and I'm sure there is plenty left in the tune, but knowing where you're at now, safety-wise, will determine how much. And yes, heads will probably get you there alone if you've got the coin right now.

Looks like you may be in for more dyno time.

 

Heads and a new intake manifold. The stock heads are very restrictive. Get a nice new set, trick flow twisted wedge is what i have just havnt put em on. Easy add ons and give turbo motors bundles of power.

 

I would say that those are good numbers on a "conservative" tune and 8 PSI.

If your tune allows for it, just go to 10 PSI, which should put you at ~380 HP and call it good.

If you really want 400 HP at 8 PSI, then you need heads/intake.
Any good head/intake combo will put you at 420-450 at 8 PSI.

 

Thanks for the replies, I guess I'll have to start saving for the heads/intake/installation.. any ballpark suggestions so I start getting scared?

Here are the numbers I got, including A/F ratios:

 

I'm definately not an expert, but that seems pretty conservative up top. Thats not a bad thing, you are less likely to blow a head gasket or hurt a piston. Taking that A/F to 11.3 in the upper RPM's would gain you some power and still be pretty safe by most peoples standards.

As far as heads, if you can install them yourself it will be around $1500 for the heads, ARP studs, gaskets, rockers, etc. You might want to save a little longer and go with the whole Trick Flow kit that comes with heads, cam, intake and all related parts to install. Not a bad deal around $2K if ya shop around.

Good Luck!

 

If you only want 400rwhp from a setup on 8psi, just add some used GT40 or GT40P (as long as they work with your headers/manifolds) heads that you can find for dirt cheap and a used aftermarket intake. If you can swing the ratchets, you can do this for well under a grand including gaskets and new bolts/studs.

 

that seems about right for the altitute, and octane available.

What I would do:
Enjoy the car as it is.
Upgrade the cooling system.
Have a set of headgaskets/studs ready for when you blow them.

The car has a very good torque curve. Take it to the track and youll be able to pull some mid 12's with no prob.


If you really want the 400hp:

Upgrade heads to some thick deck iron heads (will help with detonation) like the world windosors.
Upgrade Intake manifold. Id do something in the lines of a Holley intake.

 

I would bump the boost up to 10 psi with that tune... that will give you the 380 ish numbers you want... that is really fat up top also, so be sure to short shift it or it is just going to lay down on you.

 

Have you considered water injection? It really lowers the chance of detonation, thus allowing you to run a more favorable a/f ratio and more boost safely. Also how much timing are you running.