Exhaust Systems and Back Pressure

[Jim-ME]

I have been lead to believe that unless you have the correct mount of back pressure on a Series engine that you will burn exhaust valves. It would seem to me that headers and less restrictive exhausts which reduce back pressure would be like asking for a valve job. I'll admit that this was told to me 30 years ago by my origional Rover mechanic was he correct or just making sure that I'd continue to buy my mufflers from the dealer?

[BackInA88]

Switching to headers can lean out the mixture and if not adjusted this is what can burn out the valves.

At least this is the way I remember it from my hot rodding days.

[singingcamel]

both of you are dead nuts on...

[msggunny]

I will let you know the next time i pull my head. Running headers to a glass pack, just about as low restriction as you can get with out going straight pipe.