Fuel

[02GTPman]

Ok i have an 02 gtp with downpipe high flo cat high flow exhaust intake and a 3.325 pulley on it but when ever i laugh off the line i like bog out and get really crappy 60 footers compaired to when i only had the exhaust the mechanics i have talked to say its i need a fuel pressure regulator and a air fuel gauge because i am running to much air not enough fuel is this tru ? and i wanted to know what the stock fuel pressure should be for my car and if there is a fuel cut off because of extra boost i am running a stock ecu btw

[gprixgtp]

I may be wrong but with that pulley size you need a reprogrammed pcm. No matter how many pressure regs you put on the computer will only allow a certain mixture. It is not designed for the amount of boost you added with that size pulley. When you bought that pulley the people you bought it from should have informed you, If you bought it used that is probably the reason the other guy got rid of it. He did not have a reprogrammed pcm. The pcm is like a hundred bucks now. Get one and I'll bet your problem will go away. Those in the know here will certainly tell you if I am right or not so listen to what they tell ya here, they do knowwill point you inthe right direction.

[richtazz]

GTP's have a fuelpump resistor as well, that allows increased fuel pump putput under heavy throttle which may be the cause of your bog. I'm not that knowledgable about mods, but there's a couple guys that will be on that I'm sure will confirm what gprixgtp said, as it sounds right to me too that you need a reprogrammed PCM. Since I'm not 100% sure of that, I'll leave the final verdict to the modding experts.

[BNaylor]

From my experiences a stock GTP fuel system has enough fuel pressure to handle a 3.25" SC pulley. I agree with gprixgtp that any pulley size below 3.4" should not be used without a re-programmed PCM. Sounds like it is the problem.

As mentioned, the DHP is around $99 and ZZP has one for around $75.

Also, what size is the downpipe and the inlet/outlets on the hi-flow CAT?

[02GTPman]

Both are 2.5 inch can u give me link to a DHP destributor? cause i would like to buy that asap ... will i still need to buy an adjustable fuel regulator and air/fuel gauge if i buy the DHP?

[BNaylor]

Originally Posted by 02GTPman

Both are 2.5 inch can u give me link to a DHP destributor? cause i would like to buy that asap ... will i still need to buy an adjustable fuel regulator and air/fuel gauge if i buy the DHP?

2.5" for exhaust is just right. The adjustable FPR is recommended but not necessary. Instead of getting just an air/fuel gauge, I'd recommend getting a scanner type gauge that will monitor knock retard (KR) in addition to air/fuel.

For the PCM and other items try 3800Performance.com, pfyc.com or ZZPerformance.com.

Good luck!