With the initial success of the Gran Sport, Buick added several variants when the 1968 redesign occurred. Now available as the California Gran Sport, Gran Sport 350, Gran Sport 400, and eventually the Gran Sport 455, Buick had a GS for everyone. The top-of-the-line GSX offered more torque and standard equipment than any other muscle car of the era. But if you want to bring your GS into the modern era, we have everything you need to bolt a Gen III/IV LS between the framerails.

Depending on your choice of sound, we have patented and proven chambered muffler series that deliver mild, moderate, aggressive, and very aggressive sounds. And unlike other muffler manufactures, we offer numerous muffler models which can control the drone, also known as interior resonance inside the vehicle cab area. Check out all the different series mufflers we offer and find the ones that are right for your vehicles.