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Picked up a 2012 JK for my youngest girl. Drove from FL to VA - 900+ miles - with that insane drone. 37s with 4.88 gearing, once I hit 70mph at a bit over 2500 rpms, the drone would go away - only to return whenever I went in the 1900 to 2400 rpm range. Deafening, to say the least.

I had a pair of SuperTrapp WaveTechs laying around (5" wide chrome bell, 2.5" inlet, 8" overall length, 4" disc packs, and fully enclosed end cap) and gave them a shot. Removed the tips from the Flowmaster Outlaw, substituted the SuperTrapps with 6 discs each and no more drone. Everything I wanted - a deep idle and slight cruise rumble (well, as good as you can get with this Pentastar), a decent notice sent to neighbors on mid-throttle to WOT, and a return of lost back pressure into the system (and the restoration of lower end torque).

Final tuning will take a month or two. If the exhaust gasses cast a sooty finish to the inside of the bell, I've got too much back pressure and will need to add a few discs to each side. If the finish is a chalky white, it's too lean and needs to have a disc or two removed. The finish on the inside of the bell should mellow to a light metallic tan - which means it's just right.

I was toying around with substituting a glasspack for the resonator to kill the drone - and final considerations were moving toward a laminar flow muffler (the latter would have worked decently, I think) to replace the resonator.

I like the look of the dual outlets that the Flowmaster provided. With this proof of concept done, I think I'll try to find a set of black finished SuperTrapps to finalize the look of the exhaust.
 

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Picked up a 2012 JK for my youngest girl. Drove from FL to VA - 900+ miles - with that insane drone. 37s with 4.88 gearing, once I hit 70mph at a bit over 2500 rpms, the drone would go away - only to return whenever I went in the 1900 to 2400 rpm range. Deafening, to say the least.

I had a pair of SuperTrapp WaveTechs laying around (5" wide chrome bell, 2.5" inlet, 8" overall length, 4" disc packs, and fully enclosed end cap) and gave them a shot. Removed the tips from the Flowmaster Outlaw, substituted the SuperTrapps with 6 discs each and no more drone. Everything I wanted - a deep idle and slight cruise rumble (well, as good as you can get with this Pentastar), a decent notice sent to neighbors on mid-throttle to WOT, and a return of lost back pressure into the system (and the restoration of lower end torque).

Final tuning will take a month or two. If the exhaust gasses cast a sooty finish to the inside of the bell, I've got too much back pressure and will need to add a few discs to each side. If the finish is a chalky white, it's too lean and needs to have a disc or two removed. The finish on the inside of the bell should mellow to a light metallic tan - which means it's just right.

I was toying around with substituting a glasspack for the resonator to kill the drone - and final considerations were moving toward a laminar flow muffler (the latter would have worked decently, I think) to replace the resonator.

I like the look of the dual outlets that the Flowmaster provided. With this proof of concept done, I think I'll try to find a set of black finished SuperTrapps to finalize the look of the exhaust.
Nice! Thanks for sharing:thumb:


-Steven
 

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Good to know. I got a Dynomax muffler for my JK and swapped it back for stock because of the drone. I would like a system that does what you have done to yours. Thanks.
 
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