Cool, thanks for your reply. I'm pretty sure it's some kind of exhaust leak. I'm gonna put it on the lift this week and see what I find.

 

monolithic catalysts have a cells/square inch rating. I assume a high flow cat would have less cells per square inch which means less surface area assuming same depth in direction of flow. Fewer cells per square inch also results in lower destruction efficiency. Other factors being equal, fewer cells per square inch results in less pressure drop across the converter, resulting in a less restrictive and less effective converter. That converter probably works well at idle.

 

Attempting to post pics... Anyone know the right way to use these clamps from buschur?

 

Just a thought here... you might want to check in the trunk area, drivers side behind where the Rockford Fosgate sub sits, behind the carpet. There is a square flapper thing that relieves pressure when you close the trunk/doors or something. If that is missing or has fallen out, and you drive with the windows down or cracked it will suck tons of exhaust smell into the car.

Took me forever to find that issue in my car hope it helps

 

Thanks...I'll check that.

 

Looks right. Take the rattler to it. And by rattler I mean impact gun.

 

Well there's your problem right there...

 

Grab a flashlight and start looking under the car, you should be able to see black soot around the leaking area. Also see about new gaskets or adding exhaust sealant paste in between parts. I have a test pipe and I only smell exhaust when sitting still.

 

Thanks! Yep, i definitely found some leaks so I had all the joints welded. Much better now.

 

Spot welds? What was the reason for the leaks?

 

Sounds like an exhaust leak, possibly needs a tune

-Ethan

 

Ya so this has been basically solved through a combination of things:

-I could't get the slip-on clamps that I used from the catback kit tight enough, and they were leaking slightly. The bolts stripped when I torqued them...so welded the junctions
-The seal between the cat and the catback wasn't aligned and tight enough. This was an easy fix
-Finally, I moved back to the factory cat - which sucks but strong exhaust smell is worse.

I do think there is a possibility that my tune is too rich/could be more lean. I have a wideband kit that I'm going to install soon and will start logging to find out for sure.

I appreciate all the posts and the help!
Finally, wanted to give a shout-out to ETS - their customer service is top-notch and they were super helpful throughout. I would highly recommend them as I know they stand behind their products!

 

Did the same. I'll give a shot to an HFC, but with my old TP I can't breathe.