2004 Grand Prix GTP mod ideas?

[aaron7]

Well I see there are all sorts of things out there for my GTP... but I don't know where to start.

First, if I get the SLP headers and catback... can I use that with the stock ECU?

Second, same question for the K&N intake kit.

Third... I think I can go one pulley size smaller with the stock ECU... but how small?

And lastly... I've seen aftermarket chips that require the above mods before use... is one of those worth it?

And any other input will help! Thanks!

 

[ajaciuk]

You can use the stock ecu w/all of those things. It would be helpful if you had a tuner so you could change the parameters in the ecu. Headers and catback are very good but expensive. I would do the intake first, contact Tinman on this site he has great kits for the cars. I had a Regal GS with kit from him and it worked great. You can put a 3.4 pulley on with no problems as long as you open your exhaust a little, (get rid of resonator) go with a step colder plugs and go with a 180* thermostat I put 2 small holes in mine to help with constant flow. All these things will help control the KR you want to avoid. It all depends how much $ you want to spend. They don't make chips for these cars you can get a replacement ecu but a tuner is much better.

1. Intake around $150 just guessing
2. Pulley $65
3. Exhaust $50 local shop
4. Plugs $40-$50
5. Tuner $500 also need laptop

 

[Daniel Jost]

The things i have found that worked best, when me and my friend were modding his car were a step colder plugs,160 thermo,ZZP computer,3.4 pulley,U-Bend Delete, Replaced plug wires with MSD 8mm while he was at it, K&N intake, He also took off the engine cover so you dont have a insulator holding heat in.

With that exact setup it ran 13.9 on street tires.

Dan