Turning in my man card... I want to make the GTRA quieter... best method?

[Cobra4B]

The car is damn loud... there are mufflers in the side pipes, but they look to be some sort of bullet race muffer or cherry bomb setup. My father and I both ues the car and ride together. We found our headset was useless as the mic picked up too much exhaust noise and blasted it right in your ear. Even alone the car starts to give me a headache toward the end of a stint. It might be ok if the car was actually going somewhere fast, but 4th and 5th on the long straights of VIR (our home track) get very loud.

Our last time out the fuel pump started to cut out so I drove my fathers stock C5 Z06 out there... it was refreshing to be in a fast quiet car again. Don't get me wrong I love the Panoz for what it is, but she needs a power boost and less noise.

So.... after running Synergy in 2 weeks we'll be doing to top end of the car and re-doing the suspension. While she's under the knife I want to make the car a good bit quieter w/o scrificing performance.

So... do I cut out the mufflers and replace with quieter ones? If so, which ones?

Or... do I look into some kind of spiral flow tip inserts?

I want to do something simple/cheap... it's be nice to do as our buddy in New Zealand did and run the exhaust out the right side of the car, but don't want to get into al of that.

Thanks,
Brian

[NZGTRA17]

Brian,
the really sad part about the stock GTRA mufflers is that not only are they loud, but they are heavy and also kill horsepower, particularly on modified engines. As we found on the dyno with my car after the engine was modified, it picked up 20 ftlbs of torque and 12 hp when we cut the mufflers off and re-ran the car.

I have had great results with Spintech mufflers and Superflow mufflers. The Superflows are probably a little quieter but depends on the series that you get. The Spintechs made excellent power on my last race car, 308 cube motor that was 466rwhp on a Dynojet dyno. I would not hesitate to use either of these brands and have used a 4" in/out Superflow for my new Panoz system. Car sounds great but is still reasonably quiet.

[Cobra4B]

Thanks for the feedback... I'll look into both. Is the muffler on the car stock a chambered setup or a straight through pipe? I assumed it was just a straight shot through.

[NZGTRA17]

The mufflers that we cut off my car were straight through type that had louvres punched out into the oncoming gas stream. Yours may be different though. This style of bullet (punched out louvres) would have to be the most restrictive I expect.

[Squerly]

Hi Brian. Like you I am used to a high hp car that quietly whooshes on by with just the right amount of rumble... So I dumped the mufflers on my GTS and replaced them with a larger set of SuperFlow mufflers. The sound reduction has been much enjoyed, not only by me but by everyone that I pass under full acceleration. Don't get me wrong, you still won't "sneek" up on anyone with this thing, but it sure is a lot better.

I also got a set of tips that point the exhaust to the ground but I haven't installed them yet. I'll let you know what they add when they're installed.

[glenbinegar]

Hi Brian, G8rbob and I replaced our mufflers with Flowmaster Delta 50s. The sound is not quiet, but it is not abusive. I'm sure a few people on the forum have heard the car, we'll be at South Carolina Motorsports event this coming weekend (Fri. Asphalt Ventures lapping and Sat & Sun TZC/THSCC). We like the sound. G;-)

[Gatorac]

Screw that. Cut the mufflers out and plumb the exhaust right to your helmet. The sound is awesome. It makes me willing to deal with the current lack of power.

[jmimac351]

Brian, I've researched this because I want something quiet for my '92 Mustang on the street. The Dynomax Super Turbo is about as quiet as you can get while maintaining performance.

Jim

[Cobra4B]

Originally Posted by Gatorac

Screw that. Cut the mufflers out and plumb the exhaust right to your helmet. The sound is awesome. It makes me willing to deal with the current lack of power.

That made me laugh Thanks for the responses guys... will look into all the options. I think I'll bring ear plugs for VIR weekend after next.

[Cobra4B]

Looks like the flowmaster 50s are offered with a straight in/out design which is what we'd need to replace the muffle rin the panoze whereas the dynomax super turbo only comes in an offset setup.

I've always heard that flowmasters suck donkey balls for performance apps? True? Thought the joke was that flowmasters don't flow.

[eric1h]

keep in mind any chambered muffler will hold more heat something to keep in mind with these weak a** body panels and already a hot cabin

[Cobra4B]

^ Good to know.. I plan on having the pipes ceramic coated an/or fully wrapped.

[Cobra4B]

Can anyone snap a picture of their modifed GTRA exhaust? I was looking under last night and it looks like the side jacking bar takes up some room. If you used a chambered muffler like a flowmaster or dynomax how'd you mount it? did you get center inlet/outlet or side?

Thanks,
Brian

[carhauler]

Add a set of Supertrapps to the end of your side exiting exhausts. Adding them to my GTS kept me out of trouble with the sound police at Lime Rock. They definitely knock the DB's down without much effect on performance. You can buy 'em at Summit for about $100 a pair.

[Cobra4B]

^ Awesome... I'll look into them.