I noticed on the stock exhaust there is a short (maybe 10 inch) blind ending extension coming out at 90 degrees, close to the proximal aspect. I assume this is used to get rid of resonance. Most aftermarket exhausts do not have one. Would splicing in a section of pipe similar to the stock set up on an aftermarket exhaust help with drone/resonance?

 

Yes it would, but I dont know how many db's it lowers it.

 

I think helmholtz resonators are tuned to the exhaust they're made for. Bolting the stock resonator might not be yield the results you're looking for.

 

I don't know about drone. Most aftermarket exhausts don't have a resonator...but even the ones that do still have some drone with the catalytic converter. I run with an HKS Hi-Power setup (which has a built-in resonator), and there isn't an intolerable amount of drone, but it's definitely present. I'm putting a testpipe in this week, which I hear should cut some of it out. It's definitely worth a try though.

 

I swapped out my Toda midpipe for the OEM one and it made a BIG difference in drone and volume reduction. I attribute it to the Helmholtz resonator and the larger volume of the midpipe resonator.