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Jeano - 11/1/17 at 08:19 AM

I want to get my car under 100dB so i can use it on track this year.

I have repacked the exhaust and installed a muffler but im still at 105dB (North Weald measured me at 109dB)

The end of my repackable exhaust is a removalable tip . I want to change that for a reducer 45 degree bend so it can go under the car and i can make up a 3" track car system in order to reduce noise with an additional silncer on the rear.

Has anyone done anything like this or paid anyone to do it?

Also anyone know where you can get an exhaust 5" to 3" reducer. . . preferably with a 45degree bend

repper - 19/1/17 at 09:18 AM

did you get exhaust yet try if not try my mate at or look for him on facebook best in the biz

rodgling - 19/1/17 at 02:03 PM

Demand Engineering in Norwich did exactly this for my car, took 12 dB off.

StuP - 19/1/17 at 10:09 PM

Hi Jeano

My westfield was measured at 108 on the same day - I'm taking it to Simpson Exhausts in Slough in a couple of weeks, basically getting a much bigger silencer as repacking made negligible difference and I don't want to go down the route of bunging the end for trackdays. I'm expecting to get under 100db with the new exhaust and then I'll probably look at the intake to reduce drive-by volumes.

Is your idea to go around the wheel arch and to the back of the car with a silencer somewhere around the tank, before the exhaust exits centrally? I'd ring Simpson or Powerspeed in Ashford, I'm sure they'd give you some ideas - Matt Simpson is very helpful over the phone

907 - 20/1/17 at 08:16 AM

Obviously I don't know the details, but 3" does seem big. ?