Single turbo people- How do you get on regarding track noise regs?

[StavFC]

As title really. My FC currently runs a unsilenced screamer and a ERC exhaust system with a large single rear box. Obviously the car is mentally loud, far too loud for the track, so I was thinking of shutting it up a little (even though I love the noise and REALLY dont want to get rid of it ) just so I can use it more often, as at mo its restricted to (most!) drift days and the road.
 
I was thinking adding a large middle box and also a large/long silencer to the screamer pipe, and I know on friends 600bhp piston engine cars this is usually enough, but you know what rotaries are like :Hammer
 
So... Any of you guys who still manage to pass track noise regs on big single turbo converted RX7s, could you please describe your exhaust system so I could get a rough guide on what will be enough silencing?
 
Cheers

[rx jamie]

plumb you screamer into the down pipe that will massively reduce noise anyway. my super dragger system has a bung that i can put in the silencer and that helps loads aswell.

[StavFC]

I dont want to plumb it in or run a bung, both will be restrictive to exhaust flow, which is the last thing I want to do.

[mx1311]

pluming it in will loose you 20-50hp, run a seperate silencer

ive got a hbp gt42 with 4" exhaust front to back and have a 15" long 4" midbox and another mid box as a backbox with a dolphin tail welded to it

102.7 db static

have not got round to making the seperate system for the wastegate yet

[StavFC]

102 static still! Jesus! Makes wonder if its worth even trying, lol

[Initial-D]

Got a link for said silencer?
I currently run the Greddy/Trust silenced midpipe with 94mm piping its quiet ish but obviously you may get better flow through through your midbox? I get 102 also.

[mx1311]

got them both from reworx mate. one left over from max\'s nippon build, one off phil g\'s car


http://www.burnsstainless.com/UltraliteMuffler/ultralitemuffler.html

[suba]

This also depends on the track - Bedford autodrome has an 87db drive by test with sensors on the track, and a static 101 test.  I doubt any car with a screamer pipe would meet this, likewise if you are running a 4 inch exhaust.....