Ok, i bought my Rx7 about 7 months ago from my friend that was moving away to college and he took the cat off when he owned it. Now i heard from him and others that taking it off adds more horse power. If this is true then i was wondering if there is anyway i can make it quieter becuase it sounds awful and i dont want to smell like exhuast anymore after getting out of my car but i still want the horse power it offers. Any help please?

 

have u tried a silencer?

 

www.racingbeat.com

 

If you have exhaust smell in your car you probably have a leak in the exhaust... I've also heard that if the seals behind the tailights are bad exhaust fumes will come in there but... I'm thinking that's much less likely. A leak would also make it quite noisy. Mine was the same when I bought it. The PO had taken the cat's out and welded in a straight pipe. It was a reall mess under there. I wound up buying the original exhaust off of another FC and all new gaskets... cleared it right up and the inside of my car smells MUCH nicer now.

Also, If you have a non-turbo S4 (86-88) your 5th and 6th ports will not function properly unless he installed a straight pipe or pre-silencer with a connector for the split-air pipe and reconnected it.... which i kinda doubt. Without those working, you may actually be losing top end HP. There is another thread about that issue here:

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/5th-6th-ports-622492/