Who knew...? 2nd cat inside OE muffler

well... it sounds much better. Slightly beeper and mellowed a little. Even has a burble now as you let off the gas. Just a tad louder under hard acceleration but in a good way. Almost stock sounding just riding along at 60-75.

Good bit of labor for this mod but feel it's worth it for the time. Keeps my exhaust desires under control for the time being.

Performance wise it did feel slightly more responsive. It higher RPMs and pulling away at speed it feels like it's not choking. So guess the real benefits are at higher RPMs and exhaust being allowed to exit better.

@Nemesis1701 I thought about the possible rattle some more and have two other possibilities.
(1) the main inlet pipe is welded to the inside wall of the 1st camber. If this weld broke free it could allow the inside edge of the inlet pipe to rattle against the inner wall of the muffler producing a rattle.

(2) If any of the support retainer springs had popped loose they will also rattle against the muffler wall producing a sound similar to ball bearings as well.

Short of the things I have listed I can't think of anything else. There were no visible weld flashings or splatter that could have broken free.

little update. The drive in this morning is the real first long drive with tbe modified OE muffler. WOW what a heat reduction. By making bypasses around the 2nd converter the heat just does not get generated inside the muffler. Really night and day. Even with tbe 16.5 heat shields and deflector I still had a lot of heat flowing into the glovebox. Not today so I consider this mod a success just for this reason alone. Seat of the pants Dyno feels an increase as well but no proof .

@Live-a-Little! honestly if or when a vendor has the time and resources to design a SS specific muffler that mounts in exactly the same as the the OE they will have a winner.
Same packaging just a better flow would be a design I would be interested in.

Modding an OE is just a PITA...

Quote from Nemesis1701

They should also design better side access to the muffler as for ease of removal instead of having to remove complete side panel. Stock muffler can not be removed unless you remove side panel. Some argue complete removal is not necessary but by not doing so stress will damage or break plastic tabs. 2c

agree based off what I just did.
@Nemesis1701 I thought about your rattle a little more. Did you remove or press out your down pipe cat?.... maybe it was pcs broken loose from that?

i can break the rear tire loose easier going from 2nd to 3rd.... winner!

@dudley4 I have enjoyed mine for some time now. It is going to take something very special to ever replace it at this point. Most of the benefits of the aftermarket ones without all the issues.