The difference between the 04-05 gtps and the 06 gt is just the badging on the car. The 06gt is supercharged just like the 04-05 gtp's and they have the same horsepower. They drop the GTP badge for 06 and up until the new G8 comes out which will replace the grand prix in either 2008 or 2009.
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Exterior- stock painted black wheels, clear corners, stainless steel grill, cross and drilled front and rear rotors with evolution brake pads.
Coming soon- 18 inch black mustang bullet rims, GT/GTP rear bumper, tinted windows.