[Hotfingrs]

Actually Jim used my car as his prototype for the Cobra. Do they work?? Maybe. I think it all depends on the state of tune of the engine. It did quiet my car down. At 15' at idle my car was 104 db, with the STB installed, I believe it went down to 97 db. At the drag strip, was a different story, I lost 16mph and 1.5seconds in the 1/4. A mild output engine could possibly benefit from these, but IMHO and engine such as mine, will probably lose some power.