How Loud is Your Cobra ?

[Sidekick]

If you want it quieter you have to go with smaller dia mufflers.

If you have a 427 you need a minimum of 3 inch dia mufflers 3.5 would be better (no bigger). With 500+ HP 3 inch work well but are loud. Superformance come with 2 inch int. dia. mufflers and they suck about 100 HP out of the motor at 6000 RPM.

Smaller is quieter....period. No packing or other BS internals are going to substantially make your car quieter. if you're will to give up some more HP go smaller!

[Roger Bray]

Originally Posted by Sidekick

If you want it quieter you have to go with smaller dia mufflers.

If you have a 427 you need a minimum of 3 inch dia mufflers 3.5 would be better (no bigger). With 500+ HP 3 inch work well but are loud. Superformance come with 2 inch int. dia. mufflers and they suck about 100 HP out of the motor at 6000 RPM.

Smaller is quieter....period. No packing or other BS internals are going to substantially make your car quieter. if you're will to give up some more HP go smaller!

Forget the quieter idea. If I have to give up 100hp then I'm staying with what I have

[Dwight]

A cop heard me 3 blocks away when I spun it to 5000 rpms. Got pictures to prove it but no ticket. A buddy of mine would wait in his driveway till I got onto the hiway and opened it up a little. He is one and half miles away and could hear me.

Now I've changed the 2 1/2" x 24" mufflers for 3" x 28" and I'm a lot quieter.
I believe if you add a longer muffler your exhaust noise will be less.

Dwight