Thank you for posting this. My ‘65 GoGo coupe didn’t have a muffler - just a resonator. It was quite loud when you were on it. I have been told many times by early A experts that all 235hp motors had a muffler. This makes me feel much better. Some where, there was a magazine article that commented on this, but I cannot remember which magazine. I am currently running a replica resonator only on my convertible, and it sounds close to what I remember. Since it’s a reproduction, I’m pretty sure any difference in sound is due to that. At one point I welded a ”dump” on my high school car just past the junction of both pipes. The car was quite a bit louder with the dump open, but it wasn’t a problem at the drag strip. My convertible is not too bad as long as you don’t get on it, but when you do, it makes a great sound - and gives me the same grin I had in 1966 when I would punch it. My high school care was a 4-speed coupe, and when I would rev it and dump the clutch, the sound was amazing. Not to mention all the blue smoke from my bias-ply tires! I wish my convertible was a 4-speed and not a 904, but it still sounds good.