Not got an impreza yet (next week hopefully). Need to decide which backbox to buy. I want it to flow freely, I will be installing it with a Scoobsport downpipe and P1 centre section and ecutek remap, but I don't want it to be in danger of failing track day noise tests.

TSL do a backbox with a bolt on muffler. Ideally I'd like to use one without a muffler as on track I don't want to compromise the power. Can I get away with a different backbox (which one?) or do I need to buy one with a muffler?

Any advice gratefully received.

 

...a backbox without a muffler ...and you want it to pass the noise restrictions on track ?

Bob

 

Well, yes! By a muffler I mean a bolt on appendage that reduces the noise of the backbox.

New to the scooby scene but have been to numerous trackdays where scooby owners are running non standard backboxes without any visible add on muffler. I think!?

 

I think you may mean 'bung' which some people use to reduce noise levels?

I think the question you need to ask is what bb people use and whether they have any problems with noise levels on track.

I've not had any probs with my de-cat mongoose system with 4" bb.

Bob

 

I have a DeCat ScoobySport Down Pipe (unlagged) a H&S Afterbuner Non-Resonated centre section and an Original H&S Scoobysport Back Box. I made 103.6DB's (it was still climbing) at Castle Combe It isn't that loud inside the car but the Zorst is definately higher pitched than say a Blitz, HKS and Magnex. I would say contact Hayward & Scott and see if they can make you something to your specification with say a bung included.