SLP PerformancePac, 2005-06 GTO ''Loud Mouth II'' Exhaust 490HP.

SLP has taken the guesswork out of upgrading your 2005-06 GTO to 490hp (flywheel) with the 490HP PerformancePac™ from SLP Performance Parts. Each 490 horsepower package includes our SLP/L92 Cylinder Head-and-L76 Manifold Package, pushrods, Blackwing™ cold-air filter, complete header to cat-back exhaust system, 160° thermostat, harmonic balancer/under-drive pulley and a DiabloSport II Programmer with SLP Custom Tuning that will allow you to plug in and download the custom SLP 490 hp tune into the vehicle. All of these components work together to significantly improve performance without adversely affecting drivability. Best of all, you'll save $125 over the cost of purchasing the parts individually!