[HI Cobra]

MaSnake,

If you have the original side pipes from Classic Roadsters you need
something less restrictive. Take a small mirror with a bright flashlight
and look in the outlet of your side pipe. My originals had a plate with a
1 1/2" hole in it - you can see it easily. I got the new ones from Don
Scott and there was no restriction. A little louder (especially when you
get on it) but they sure released a herd of ponies. Fix that problem and
you will be pleased. Mine are still fine for in town driving, just keep the
rpms down.