Triad/SSI/Header Resonance Fix

[rpankhurst]

A while back there were a few posts about resonance problems with SSIs/Headers and Triad mufflers. I own a Triad with 3" tips and RSR headers and also have noticed significant (my wife says deafening) resonance between 2100 and 2800 rpm especially under full throttle.

I decided tonight to try something to reduce the resonance and it appears to have worked. I plugged the left outlet with a 3" drain cleanout plug from HomeDepot (~$4) The car now exhibits minimal resonance over the complete rev range. There doesn't seem to be have been any noticable performance impact in my drive home.

Triad owners - head to Home Depot for resonance relief!

Cheers,

[widebody911]

You can reduce resonance even more by plugging both outlets.

[rpankhurst]

Thom -- Is that how you guys keep under the noise limit on those West Coast tracks?

Cheers,

Richard

[dd74]

Originally posted by rpankhurst
A while back there were a few posts about resonance problems with SSIs/Headers and Triad mufflers. I own a Triad with 3" tips and RSR headers and also have noticed significant (my wife says deafening) resonance between 2100 and 2800 rpm especially under full throttle.

I decided tonight to try something to reduce the resonance and it appears to have worked. I plugged the left outlet with a 3" drain cleanout plug from HomeDepot (~$4) The car now exhibits minimal resonance over the complete rev range. There doesn't seem to be have been any noticable performance impact in my drive home.

Triad owners - head to Home Depot for resonance relief!

Cheers,

To me, corking one of the outlets belies the purpose of having a dual-out exhaust. Resonance is part of the deal of switching to a Triad. I don't know about other dual-out mufflers, but owners of Triads have stated the system "booms" at the RPMs you describe.

With that said, it was suggested that cutting the tips slightly might rid the exhaust of its resonance. I'd try that instead of plugging up the exhaust.