Can I open up the sidepipes?

[DaveR]

scottj

I'm always impressed by mechanical ingenuity. Sounds like something I would do(and may be doing in the future). I'm a little surprised that an increase from 3" to 3.5" makes that much difference in performance when it's that far back from the engine.

[scottj]

DaveR,

The 3" core I had was louvered like Blake discribed and while the pipe diameter was 3", it only measures 2-3/8 or so when you consider the protruding louvers. My pipes are a true 3-1/2 straight through.

The difference I noticed was a slight carb stumble and fewer revs than with the 3-1/2's.

If your going to do it and want some muffling, go with 5" pipe. 4" pipe was a whole lot of work for next to no muffling at all.

[DaveR]

scottj,

Yea, 2 3/8" up to 3 1/2" is a lot. Thanks for the input, it's a big help.

[Blake Olson]

I actually removed all the "glass" from inside my pipes...is it as loud as I wanted, no, but it's better...better performance as well.

blake

[DaveR]

Blake,

I used to ride my motorcycle in Austin. Great roads for a Cobra!

[Blake Olson]

The hill country has GREAT roads for the cobra!

blake