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99 GTP Mods questions.

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newbiegtp

New member
So I have a 99 GTP. The current mods are 4" intake, 3" downpipe with cat and u bend delete, 1 degree colder spark plugs with upgraded wires, I've wrapped the crossover and will be adding a custom throttle body heat shield, wideband o2, and a custom tune.

My goal is to get 300+ WHP. So I'd be happy with 305 WHP. I am looking into buy the VS cam from ZZP because I will be mainly driving it on the street and maybe once in a blue moon take it to the track. My list of purchases are as follows.

* VS cam
* New Springs, Seals, and locks. Going with stock or 85lb springs.
* 3.4 modular pulley
* New custom tune

My real question is should I purchase 42.5# injectors with this setup or will the stock 33# handle them, and should this break the 300 WHP mark?

If this is already a thread sorry for reposting.
 


I think you can get 305 without doing a cam. to my knowledge a full exhaust and intake with a gen 5 supercharger and 1.9 rockers with a 3.4" supercharger pulley will get you there.
 
Wont even come close to 300whp, maybe 250........maybe....... with what you have listed.


You need flow mods to run a cam.

Buy some headers, skip wrapping the crossover and screw the tb heat shield, the blower super heats the air anyway, you cant stop it.

So here is how I would do it.

Headers
vs cam
prolly L76 springs
Ported blower
3.4 pulley
AL 104's
and a Wideband Tune

You might get away with stock injectors still, you would just have to see.

Even with those mods, you may not even get 300 WHP more around 270-280 whp, and when you get that high, transmisson failure rate goes way up.
 
Fivefingerdeathpunch said:
Wont even come close to 300whp, maybe 250........maybe....... with what you have listed.

Even with those mods, you may not even get 300 WHP more around 270-280 whp, and when you get that high, transmisson failure rate goes way up.
Click to expand...

I agree with not reaching 300 WHP it was a goal that I'm shooting for and will continue to hunt it down if I don'r reach it with this upgrade. So yes I agree I will most likely land in the 270-290 area. Thanks for the transmission warning. It was replaced approximatly 15,000 miles ago so should be ok because I rarely race or go to the strip.

My main areas where I was having issues on proper information were injectors being able to hold up and the valve springs. I've read a few times but actually having someone say it helps that injector sizing really just depends on the car. So I'll just have to hope mine work or go with a mild tune and save up for new ones after the build. As for the L76 springs I was looking at upgraded springs so I avoid valve float at all possible. I have one question and that is will the L76 springs work with stock retainers or will I need new ones?
 


johntremell said:
I think you can get 305 without doing a cam. to my knowledge a full exhaust and intake with a gen 5 supercharger and 1.9 rockers with a 3.4" supercharger pulley will get you there.
Click to expand...
I am looking at avoiding the Gen V supercharger for now as I am a broke college student. I may purchase it later in life when I can afford to really add performance. Thank you for your reply.
 
You will need an intercooler and a much smaller pulley to reach 300whp with the VS cam. Preferably a stage 2 intercooler.
 


newbiegtp said:
I am looking at avoiding the Gen V supercharger for now as I am a broke college student. I may purchase it later in life when I can afford to really add performance. Thank you for your reply.
Click to expand...

A cam is 800-900 if you do the install yourself.

Intercooler its well over a grand. You'll still want a larger tb by that point.

that's another 300.

Gen v is only another 300.

Use l76 springs and ls1 retainers.

All in all the comment I quoted its funny.

You'll need injectors but I don't recommend the Lucas 42.5's.

Get 60's or better ~40's.
 
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