exhaust advice needed

Hi,
I was wondering if anyone can give me some advice toward quieting my exhaust system.

My car is a recently-built ITS 86 GTU, and I've only taken it to two tracks so far. At the first track I never got a black flag for sound, but the second event I got flagged for 104dB. The header collects to single 3" dia, and goes into a custom pipe with a Dynomax 6" OD muffler. Initially I removed the Dynomax and slapped on a Flowmaster but it was still at 104dB. Luckily someone at the track had a 3" 90-degree turn and I was able to attach before the Sunday race and it got me by.

Ideally I'd like to be able to get the car down to around 100dB or less (hopefully with negligible HP loss) so I don't have to mess with turns or worry about being too loud. Of course I also don't want to spend much money or toss parts I already have. I think the header was made by Racing Beat but I don't see one on their website that collects to 3", so maybe it was custom, or maybe I'm wrong. Someone else designed my exhaust system, and he normally does 1st gen ITA cars and said "you'll have no sound issues". Is the 13B that much louder than the 12A?

Anyway, should I try a 4" or 5" pre-silencer before the Dynomax? Should I chuck the whole system and go to dual exhaust (ouch! $$). Or should I stick with a turn and deal with the worry?

Thanks,
Mike

Well cost wise, I say stick with the turn down. For a point of reference, I run a Racing Beat dual header, ICS collector and Dynomax 3" muffler. I have yet to fail sound check. At Mid Ohio I was reading 98-99.

Pauly D

Pauly, what's you reasoning for using a Racing Beat header into a ICS collector ? I'm converting from Spec-7 to ITA/7.

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David

Well I am driving a `91 ITS RX-7. The Racing Beat header is the dual outlet type and the ICS collector is a perfect fit. The Racing Beat header is a bit cheaper than most custom fabbed units.