Fabspeed Shelby GT500 Sport Catalytic Converters (15-20) (FS.FORD.GT500.SC) 2543 the R1 is designed to

the R1 is designed to be the last DV upgrade the engine will ever need

smooth precise feel

Patented AQP elastomer smooth bore inner tube

This is due to a change in the design of the factory exhaust system for 2007

the system comes with quad 4

Fabspeed Shelby GT500 Sport Catalytic Converters (15-20) (FS.FORD.GT500.SC) 2543 the R1 is designed toThese Shelby GT500 Sport Catalytic Converters are the perfect solution for any street and track focused GT500 owner. Adding significant power and sound, you have the option to go with ultra high performance HJS Catalysts. There isn't much to improve on the intoxicating sound of the GT500 until now. Adding a significant increase in power, tone, and sound, these high flowing Sport Catalytic Converters give unrestricted flow with NO CEL (Check Engine