This is my 2005 Grand Prix GTP with all the bells and whistles along with some extra goodies I have added along the way. I started with the exhaust by adding a hi-flow cat and junking my resonator and those terrible bends that the exhaust had back to a set of stainless steel hi-flow raptor mufflers and two stainless steel tips (the biggest ones I could find lol) I then added the Thrasher Modular Pulley System 3.25" TEP Modular Pulley which made the car a lot more fun. I ripped out the air box and dropped in a K&N cold air intake (if anyone is thinking about adding this, DO IT! The sound this thing puts out is worth the $$$ alone!) And replaced my PCM with a reprogrammed PCM from 3800 Performance (thanks Rob) features include,
- Speed limiter removed
- 3-1 and 4-2 skip shifts (Active in performance shift mode only*)
- Transmission line pressure increased (Active in performance shift mode only*)
- Shift points moved (5800-6000rpms) (Active in performance shift mode only*)
- Fan turn on points altered:
- Torque abuse modes are modified to eliminate bog at launch
- Part throttle KR issue fixed
- Removes lag by changing downshift tables
- 185 degree turn on
- 2 minute fan on at key-off (this feature activates when engine coolant is 180 degrees or greater)
- MAF calibration adjusted for proper operation and year
- En-richens fuel delivery for critical problem areas
- Provides a consistent power gain across the entire power band
- Reduces spark retard (knock retard)
- Removes “40MPH WOT lag”
With all these add ones the car has gained a lot of HP. stock was 260 horses but is for sure in the 300’s now and a hell of a lot more fun!

As Far as the exterior goes I have changed a few things to make the car stand out a little more than your every day GP. I started small and added black reflective Front and back Pontiac Lettering along with a black reflective Pontiac arrowhead on the hood. I then put in some Light Satin Nickel finished grilles in the front fascia. Sadly it seems that GM is throwing these in stock GP’s as well now, but aah well. I also added some GTP competition group plates on the sides of the car. I went a little bigger when it came to the back end. I added a limited addition bumper and molding (which looks great!) along with a stage 1 spoiler to top it off. Well I hope you like the car and stop by because I am sure I am not done yet….