Do I need this?

DHP-1.0....

Just checking if i should get this or not. What will it do for me and is 85 dollars shipped a good price. It's coming off a 99 GTP so I was wondering if I could use it in my 98 GTP.....

The DHP v 1.0 reprogrammed PCM module is probably the most reliably programmed PCM module on the market and the most popular for Stage 1 mods. Allows use of smaller supercharger pulley, changes cooling fans turn on points, shift points and removes speed limiter. However, there are other companies that do PCM reprogramming like Intense and ZZP.

The rule of thumb is to get one that is ready to go for your specific year model. I would pass on the deal and find one for your '98 model GTP. You will not be able to use one for a '99 GTP. The '97 and '98 models versus '99 and up have minor differences not just in programming (firmware) but internal hardware and some wiring pinout configuration at the two 80 pin connectors.

Even if you get one for your year and model it should still be programmed to include your VIN number and may need a crank variation learn procedure run. GM Tech II diagnostics scan tools that the GM dealers have will pull up the wrong diagnostics displays and parameters when the VIN and year do not match yours.

Therefore, you may be better off just sending your PCM module to DHP, Intense or ZZP to get reprogrammed.

Gotcha.. Thanks for the information...I'll just send mine out when it's time.

I put together a really nice FWI recently. It almost sounds like a grinding rotor when I'm at idle and accelerating slowly while its sucking in that air. I thought I screwed something up at first.:lol: .

My next step will be the u-bend delete. Should I do something with the resonator as well or leave it since I will be getting headers.

Also I have been reading where some people have a 3.5 pulley. Is that a step up from where I'm at stock or is that what I have. If its a step up when can I safely put one on or should I just mod for a 3.4 pulley?

I put together a really nice FWI recently. It almost sounds like a grinding rotor when I'm at idle and accelerating slowly while its sucking in that air. I thought I screwed something up at first.:lol: .

I know of a few members that made their own. What brand and size filter did you go with?


My next step will be the u-bend delete. Should I do something with the resonator as well or leave it since I will be getting headers.

It is up to you on removing the resonator. The problem is not only will the sound level increase but you get this droning type sound in the interior of the car. Not too cool on long trips. I would hold off any any major exhaust mods with the exception of the u-bend delete until the headers are installed. You will need custom work done during installation and I would go to 2.5" plumbing to at least the input of the mufflers.


Also I have been reading where some people have a 3.5 pulley. Is that a step up from where I'm at stock or is that what I have. If its a step up when can I safely put one on or should I just mod for a 3.4 pulley?

The stock is 3.8". The smaller you go equals more boost. The 3.5" pulley is the smallest you can go without going to a reprogrammed PCM module. With a 3.4" and under knock retard (KR) is a big concern and supporting mods like exhaust and intake should be done at the same time or before. IMO a 3.5" pulley is a waste of money. The best thing to do is go to a modular pulley system where the pulley can be swapped out in less time.

I ended up with a 7" K&N filter. I only have about 7 dollars into the whaole thing. A friend gave me the filter and all the ABS pipe and fittings was given to me by plumbers on the job. The only thing I had to buy was a 3" flexible coupling and a 3" to 4" roof flange. Very inexpensive and after reading up on all types of CAI and FWI I think that this has to be as good as anything else. Heck, I think its was ZZP that sold ribbed plastic flexible conduit or something. That didnt make any sense that it would be ribbed but hey, what do I know..

Yeah, and I get enough droning when I'm driving my Jeep down the highway I dont want my car doing the same...