Im a bit short for space but would like to silence the car to at least get on some circuits, so wondered if anyone had any experience of a setup a little like this and had approx db levels for it...

Ill fit the wastegate pipes with small seperate silencers- Experienced that before, and it almost totally silenced them, so that part is ok.

The main post-turbo exhaust is the issue, as I need a 4-5in system (going by the usual turbine exducer x 1.25 it should be at least 100mm/4in), but could easily split into twin 3-3.5in, but then only have room for about 25in of silencer, meaning twin 25in silencers side by side.

Although these silencers are fairly large, most track legal systems are two boxes in a row at least, but this is two silencers side by side, which wont be as effective.

Anyone done anything similar on a rotary?

If its still going to be stupid loud I may as well not bother and just run a straight pipe as I wont be able to get on track either way....

 

hm.. i dont know about that, but pointing the outlet downwards helps a lot.

 

Need to know more about your specific setup but on my current setup- high compression 13BT, GT35 w/ 3" turbine outlet

I use a 3" exhaust with a single Borla Race muffler and at idle it is very quiet, at full wick it is fairly loud but the tone is low enough that *most* places I have run it have let us off with a warning.

On a 4" exhaust a turbo car, full length, you might get away with using a 4"x21' Coast Fabrication or Burns Stainless race mufflers, if you need more silencing then a Borla or similar might be your answer.