[moore_rb]

Does anyone know or remember what the internal "flow through" diameter of the original Classic Roadsters muffler insert was/is? (EDIT: Nevermind- DV posted it above: 1 inch )

I've decided to replace my CR's originals with the 4 inch diameter Jones Bullets, but I'm going back and forth between selecting the Jones 3 inch internal insert diameter, versus going with the 2.5" insert diameter....

From a back pressure standpoint, I'm thinking that the 2.5" insert diameter is the correct choice for my car's 325HP 302... At the 6000 RPM redline, my engine can only move 524CFM of air (and that's at 100% VE, which is virtually impossible in a street engine anyway).... So anything bigger than 2.5" is just going to increase turbulence inside the muffler, and make more noise. Plus my engine is fuel injected, and the O2 sensors are mounted right after the 4:1 collectors, so I have to be mindful of flow velocity past the O2 sensors.

Sound wise - The 2.5" inserts in the 4" case means more space for packing, which should equate to more decibel reduction, and a lower pitched "rumble" ; While the 3" inserts will allow more room for the sound waves to bounce around, resulting in a more raspy, crackly, race car style exhaust note. (which I love); But I'm concerned that the 3" inserts might also yield a drone at cruise speeds (an enemy I would rather not do battle with)

Sorry for the long post- I'm just thinking out loud here, and letting you all come along for the ride... lol