I agree with the abovea few HP, not very much. There is no power inside a muffler, especially a cat-back one. The most power would come from no muffler whatsoever. So really all you're doing is getting rid of some restrictions. You have to look at a car's power train as one long tube, with an opening at one end and an opening (exit) at the other. The one end is your intake, the middle is your engine and the exit is your exhaust. If you just open up the back end and don't do anything to the front end, you really can't accomplish a great deal. But it'll sound good and you might get a little better throttle response.at least you'll think it has more power but on a dyno---I think 4 to 10 HP at high RPM is the best you'll do---presuming you have a large displacement engine. On a little 1.6 liter engine, maybe half that.
Cat-back exhaust systems depending on the OEM design car can add 10-15 hp - not much more unless you do a custom ECU tune. You should also consider a complete system IE cat-back + down pipe. The real gains are to be had with an ECU re-flash with a custom tune. for example: The factory saab 9-3 turbo 2.o makes 205 Hp - with a catback-downpipe custom tune - they easily make 275-300 - instantly. Borla actually built several systems of various diameters to get the most power out of the VWs IE they actually tested them on the dyno they found on the VWs that the smaller 2 1/2 pipe susyems actually add more snap down low in RPMs. Remus the same.Go for the Remus OR Borla if you want killer sound - Remus actually tune there german exhaust systems to sound wicked - IE like tuning a musical instrument. Remus at www.remus.at. You can go to YouTube and listne to the various sounds of exhaust systems. IE Search VW Remus or Borla. Borlas website also has audio files.
a motorcycle with flames for tires
a motorcycle with flames for tires
