2001 GTP mods

[dakotaisthedog]

I just bought a 2001 GTP and I've been trying to educate myself in previous forums on which mods are the best to start with.

Here is what I plan on doing:

ubend delete
NGK TR55 plugs
160° thermostat
Thrasher CAI
DHP PCM
3.4" pulley w/gatorbelt

Any suggestions or additions recommended? (without breaking the bank)

Now I have a couple questions...

1. Is a hi-flow cat or different exhaust necessary or highly recommended for use with a reprogrammed PCM? My understanding is that they are a lot of $$ for little HP. On the other hand, 3800performance.com says they recommend that mod with the use of the PCM.

2. I heard that it is unwise to use less than a 3.4" pulley without an intercooler. Is that true, or can I get by with a 3.25"?

3. With these mods, I expect to get less MPG, of course, but are there any other cons I should be aware of?

4. Last question! I don't have performance shift, so I'm aware that I have to rig a wire from the PCM to a switch to get perf. shift or ground the wire to the car for "always on." I have a shifter out of a 99 GTP with the perf shift button. Is there anyway to use that and hook it up to a wire going to the PCM??

Thank you in advance for any help on this!!!

[BNaylor]

Your initial list looks comprehensive and reminds me of my first mods.

On fuel economy forget it, you will lose a few miles per gallon especially if you go to a 3.25 inch SC pulley. You don't need an intercooler running a 3.25 pulley, however, later on it would be wise to go to a larger throttle body. It will help cool and improve the intake charge. IMO the 3.4 pulley is better for the street and overall driveability.

Finally, I would recommend a hi-flow CAT and the DHP PCM has programming provisions/maps to take advantage of exhaust mods. Also go with a u-bend delete. A Catback exhaust system is probably a waste of money for the hp gain but it will sound great. Good luck!





Thrasher CAI, DHP v1.0 PCM, SLP Headers,
3.25 SC pulley, CAIT GMAF, 2.5 DP/Hi-Flow CAT,
u-bend delete, 160 TS, ZZP Stage 1 72mm TB,
TB spacer, MSD 8.5mm wires, Autolite 104s,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials