My 72 Supreme 2-door hardtop (350 4-barrel, m20) has stock pipes with right side and left side mufflers different. Left is 2" in and out, right is 2.25" in and 2" out. I have had glass packs on it since high school (1989) but figure it is about time to grow up and go with turbo mufflers. Something more aggressive than stock but not as loud as the glass packs. Did some searching and I don't see much available that might be direct fit. Figuring I may need to get shorter mufflers and use the difference in length to step the 2.25" down to 2" and then be able to use the same muffler left and right. Anyone know what the stock muffler dimensions would have been? I have an old AP catalog (1979) but can't find any hits or interchanges for the muffler part numbers 892 (left) and 856 (right).

Any suggestions or recommendations would be appreciated.

 

Dynomax Super Turbo is probably the most popular muffler on here. They have a nice muscle car tone but not loud.

 

I had those Dynomax mufflers on a '74 L-82 Corvette around 10-12 years ago and they were a nice choice for a stock tone overall. Jason, if you're on FB, I'll invite you to the V Code page that I created to supplement or replace the old V Code website where I had your car listed previously.
Terry

 

Have you gone to a local exhaust shop to get a quote for installing new mufflers? Local shops often have house brand turbo mufflers that can save you some money.