What's the most HP I can get out of a GT? After all Mods.

[bcreverend]

and don't forget about modifying the rest of the car to handle the increased hp and speeds. the tranny can be switched for a beefier GTP tranny...i recomend the thrasher shift kit for harder shifts...suspension mods(springs, struts, strut tower bars) for better handling and probably most important nice soft z-rated tires to grip the road and insure stability at higher speeds (good tires will improve handling as well).

[kilroypr]

That is correct and also do not forget about braking too. What is the use of having good road grip, added power and lame brakes? In my after all the mods where installed I had to but on at least vented and ranurated rotors to enhance braking...

[kilroypr]

What I meant is that after all the mods(performance) where performed I had to install vented/ranurated disk rotors to enhance braking.

[thiefgarrett]

Originally Posted by Justin1569

If I had 1.5 G's lying around how much HP could i get out of my engine if I threw all this money into modding my GT. Please let me know here. I want a powerful sleeper, then can even beat some stock GTP's.

Basically the GT could be modded to beat a STOCK GTP and even a lightly modded GTP. Modding is not a one day thing, it takes time. You have to feel how your car is responding to it, which one's better and you'll be doing a lot of research. Everybody says something different about particular product, some would work well for some, and some don't. Also, First of all there's an order in modifying, you can't just install a 1st stage cam without modding your intake, your u-bend and DP (down pipe). You have to clear those restrictions first. A gutted airbox is one, but if you have the money try a CAI. I particularly gutted my airbox and fabricated a large openning to the fender instead of that 3 in. pipe openning. I also gut the pastic behing the air filter, now it breathes and could actually hear it whenever I start the car. I thermal wrapped the f-duct, IAT sensor and airbox too.

Second, get a DP. Like the RT DP or M and S. You'll get a 3 in. DP, a high flow cat and the u-bend deleted to a straight pipe. One of the biggest restrictions on the GT and GTP is the u-bend. The stock catalytic converter also is restrictive compared to high flow cats. You can also replace your resonator with just a straight pipe with 2.25 to 2.50 in. dia. up to the Y pipe. After these, get some underdrive water pump pulley and you could add a underdrive alternator pulley.

Third, a High Velocity TB (throtle body) is available at Intense Racing or ZZP. This one's ported with a bigger butterfly or valve for more air passing through your TB. There's a free mod in your stock TB, remove the TB screen.

Now by the time you get these, start feeling your mufflers if they're able to accomodate the higher CFMs your high flow cat is producing and the bigger intake your car is inhaling. If you change to a cat back with all mandrel pipes you'll probably add a 5-7 HP. with cat back alone. For a GT don't go too big with the pipe dia. you don't want to lose your low end torque!

Fourth, rocker arms are good up top (top end power) maybe around 15-20 HP. But a 1st stage cam or even a stage 2 is more powerful. Around 20-50 HP. depending on supporting mods like headers (TOGs). With a stage 2 cam, you'll need to chage your pistons, torque converter, valve springs, pushrods and you should have already a DHP or a reprogram PCM. But more people like the DHP. The addition of a shift kit will make your shifts firmer, DHP gives the skip on shifts. It makes driving really exciting and fun.

There are lots of mods, go to clubgp.com it's all there. Also, you cant have high ratio rockers with cam (1st or 2nd stage) unless you have the short block race ready enging. It's really hard to explain everything, reasearching and reading peoples experience is the key. 'Cause people are sometimes happy with their mod some feels like they just wasted their money.

I myself like a powerful normally aspirated enginge, it shouldn't be categorized with the Forced Inductioned cars. But then if you're really serious with drag racing or racing for that matter, then FI has the leverage. .........But then you the new GTO, 5.7 V8 LS1 engine, normally aspirated. There's just too much going on with cars.

[GTPCatz]

[quote=bcreverend] the tranny can be switched for a beefier GTP tranny...[quote]


I disagree....the GT has the better tranny or at least gearing
I think there is a kit to make the GT tranny a HD tranny....keeping the original gears (3.29) but adding a little more beef.

[GTPCatz]

Originally Posted by kilroypr

I had to install vented/ranurated disk rotors to enhance braking.

thats really optional I dont think vented brakes help you stop any better....it just helps disapate heat
If your car is a daily driver you dont need vented brakes....they look cool though!

I would go with the 12" brake upgrade....its a much better performance upgrade then getting stock vented....now you can still get vented or drilled in the 12" but thats up to you.

[98GPGT]

Well if you do a cam and rockers your definetly gonna have to have alot of head work done. Your valve hieght will be to high otherwise. Plus when doing cat back don't buy borla/slp/dynomax or whatever. You can have a custom exhaust made at almost any exhaust shop for 1/3 the price, just get some nice mufflers. Also personally if you're looking to have a fast gp don't go naturally aspired. Its not worth it. A naturally aspised FWD V6 can never be extremly fast. Also check out http://www.intense-racing.com/ they are coming out with a turbo kit in spring/summer. That can make a huge difference on your car.

[Justin1569]

I live in Winnipeg, Manitoba, Canada. We have temp extremes. Hot Summers and Cold Winters. We also get lots of snow. Will these mods be fine under harsh winter conditions. I need to know because my car is a 4 Season vehicle. And is it possible to get a list of mods to do in orderly fashion as on what to do first. I got $1500.00 for this. Please be specific and well detailed. I want to try and beat a stock GTP. Plus I kinda wanna know what my HP will be at from 200. Please & Thank You!

[BFT]

I wouldn't be so quick to do an L67 swapp right now. There are a lot of nice toys comming out for the L36 this spring. The GT can be made fast enougth to take on stock GTP's, but once they do a pulley swap..... it's all over.(At least untill the turbo kit hits the market).

[minder]

Originally Posted by Justin1569

I live in Winnipeg, Manitoba, Canada. We have temp extremes. Hot Summers and Cold Winters. We also get lots of snow. Will these mods be fine under harsh winter conditions. I need to know because my car is a 4 Season vehicle. And is it possible to get a list of mods to do in orderly fashion as on what to do first. I got $1500.00 for this. Please be specific and well detailed. I want to try and beat a stock GTP. Plus I kinda wanna know what my HP will be at from 200. Please & Thank You!

Winnipeg! Me too! I run a 2000 Bonneville SSEi (Supercarged L67) and have similar questions... where do I get the most bang for my buck and how does the performance of these mods (and gas milege) hold-up under these temperature extremes.

I'm mostly interested in better ignition and a pulley swap but need to know if I lose gas mileage with a 3.4, and if I go smaller like a 3.25 pulley does that mean I am losing even more? And if so, is it mostly worse in city or hwy? I do a lot of both.

Comments anyone?

I heard an after market PCM would likely cause a loss of gas mileage - can anyone confirm? I don't really like being regulated...was still sinking in my seat from accelaration on open hwy when my speedometer stopped at 200 Km/h (130 m/h).

Justin, I'm in St. Vital and my 2000 SSEi is a dark red metal flake with the 18" chrome mags. If you ever spot me, be sure to challenge me!

[BNaylor]

Originally Posted by minder

Comments anyone?

Man this was old thread! Last post before yours was over a year ago.
Go with the 3.4 SC pulley.

[MIGTPGUY]

i wish i could put a cam in my ride, labor is way more the the cam cost....