I have a 1970 911T with a stock 2.2. The muffler on my car is on the goofy side, and I'm looking for the quietest muffler I can bolt onto the car that sounds "good". That's usually the factory muffler (but correct me if I'm wrong).

I went in search of a used one, and came away confused by words like Bischoff and Leistritz...What's the difference between these two? Did the mufflers change over the years? If I'm looking at some muffler on eBay, what should I be looking for to ensure it's not just some crap can that may or may not fit?

I've read that most Dansks are on the tinny side, M&Ks are on the loud side, and anything with two outlets is gonna be louder than a single outlet (and could possibly drone), and I don't need much of that...The primary reason I have a 911 instead of a 912 is the sound, so I might as well try and get it right!

Is there anything else I should be looking for? My current default is the Porsche Classic reproduction, but at $1,100...well, I'm hoping I can do better on something used but in good shape.