OK, so I needed to replace my catalytic converter. I figured why not install a Borla exhaust. Although it is "custom fit" still needed a bit of "coaxing" to have it installed.

Unfortunately, it is louder inside the car than I expected under acceleration. At 70mph cruising its OK, but otherwise the droning is annoying.

Any suggested remediation?

 

It has a resonator, right? 2nd resonator ftw? Don't know of any other options.

 

Mine sounds nice. The Borla set up comes with downpipe, resonator, and muffler. I think it sounds pretty sedate for an aftermarket exhaust.

 

I was just asking because Techtonics makes a Borla exhaust that doesn't include a resonator, completely different (louder) muffler too. Badluckaudi had it and sold it to chaos i think. The AWE Borla is pretty deep/mellow but can be droneish from what I remember on Arif's car, but it wasn't bothersome imo.

 

try putting on the stock resonator in place of the borla

 

Did you replace the stock catalytic? If so, that is where the added noise would be in comparing your car with the Borla to another identical with the same Borla system.

I got so tired of the insanely loud Borla System on my exremely modified, serious Hp Mustang. It would set off car alarms as I cruised by cars in parking garages. Sort of funny, but when I was driving in Annapolis and two girls gave me a frown and put their hands over their ears referencing the sound (and I was just limping by) knew it was time to change it. I called Borla to basically say that this Borla was ridiculous and I had been happy with the sound of the one on my 94 Range Rover.

The "engineer" that I talked to (I'm and engineer) said theirs was designed to be installed with the factory cat and that any aftermarket would make it significantly louder - Headers would make it louder yet (I had BBK headers and cats).

I asked why then are Flowmaster with the same headers and cats not 1/2 as loud...

Bought a Flowmaster and put it on, it was great.

I ended up selling my Borla system - and warned the guy that it was going to be loud. You should have heard it with the off road H-pipe (no cats) on it. It was insane.

 

I thought my Borla cat-back was loud at first too. You'll get used to hearing it soon, and in a couple months, you won't even notice the sound. I think it actaully sounds better (more mellow) after a thousand or so miles have been driven with it on.
I even chipped my ECU a few months after, and didn't notice any significant increase in sound, just pull and how.

 

I'll give it a chance.

As far as the cat being the problem, I doubt it. It isn't a high flow cat and although it isn't OEM, it sure isn't the source of the problem. I may have to try a second resonator, in addition to the one that came with the Borla.

Going back to the old resonator isn't an option, its now scrap.