i run a catless, full 3" BR exhaust, so obviously i won't be passing. i'm hoping to have a "bolt-on" option for MRLS, other than just putting the stock exhaust back on.

has anyone has any luck building an exhaust that makes "okay" power (i don't need a ton) but still meets the sound limits?

all the search results i get have people theorizing, but nobody with a definite answer.

 

Call Road Race Engineering (RRE is outta SoCal, so they know how it goes) and get their 3" stealth catback and you'll be good.

 

I'll look into that option, thanks. Also hoping to modify mine to work. Thinking about flanging the muffler along with my two resonators. Maybe I can bolt on a quiet muffler.

 

I run their stealth exhaust with no cat and it very quiet, no one ever complains and from what I have seen they still make as much or even more power than some of those louder straight pipe exhaust out there.

 

run a Vibrant mini muffler in place of the test pipe.

Buy their oval muffler for rear.. or buy RSR exmag stealth.

(if you dont like my suggestions) fu** off Jason

-Gary

 

Never had a problem with my catless set-up. I run a WORKS stealth muffler.

You can "hear" it here...

 

I need to be 91dB quiet :-(

Am I supposed to know this clown?


Straight 3" with just the muffler and you passed? That makes me feel much better.

 

Yes.

You know you can also get a db reading electronics from Radio Shack to test it yourself, too.

 

definitely. i assume the sound guy to be about 50' or so at the closest? not too bad. i wonder if bolting on a turn-down tip might be a bit of extra insurance.

 

There is no "guy" per se. It's a microphone attached to a fence just after turn five, right at the start of the up-hill section.

 

I cant speak for MRL, but Lime Rock Park has an 89db limit, my Tomei Expreme TI with test pipe was wayyy over the limit. We went with a catted AMS pipe and installed a Vibrant mini muffler in it. Works like a charm, still sounds good and the best part is; no more drone when I do drive her on the street.

 

According to the rep I spoke with they now have a guy that moves around the track on an ATV and measures from different locations. Maybe I was given bad info?

 

MRLS... Mazda Raceway Laguna Seca. I get it lol. Our Sunday DE groups at Road Atlanta with the PCA run similar sound restrictions. I would just lift when going past the meter hahaha. At autox's I have had success with a large 90 degree turn down that I could point away from the meter. It was made out of some scrape 90 degree thin wall piping, that was just big enough to slip over my exhaust tip. I cut some slots in the slip on portion and clamped it to my exhaust tip with a large sleeve clamp.

I have the same exhaust as you.

 

I don't mind lifting if the meter is still stationary. If the guy moves around, I'm stuck. I'll post pics of my exhaust so far.

 

Oh, huh. I haven't been there in a while so, it's quite possible that has changed.