I have a 1975 280z built for California. Has EGR, catalytic converter. Would I get any better performance removing them? And if removed, should I advance timing from 10* to 13* ? Thanks....

 

Here's an older thread that provides some guidance: https://www.zdriver.com/forums/240z-...nt-280z-30655/

 

Thanks but it really didn't tell me much. My main thing is I am wondering if the catalytic converted is restricting exhaust flow? I think it's original and probably either needs replacing or removal.

 

Removing smog components on a stock engine doesn't do anything except fail you in California. 99% of the people who remove the EGR do it for "looks". There's no need to remove the cat unless you like smelling like exhaust after you drive the car... on the bright side, those fumes will probably kill a few brain cells.