Is it worth upgrading the exhaust manifold studs and bolts? Most of the nuts are mangled and the studs have some surface rust, I can clean up the studs but not sure if its worth just replacing them with something better. Was looking at the kit at MiataRoadster with the ARP studs.

Worth changing or just get new nuts and call ti a day, only thing is the oem nuts are pretty expensive themselves.

 

I would say most of us use stock studs with new quality nuts. These are m10 oder m12? Haven't heared about problems with reliability

 

I used the MiataRoadster kit this past off-season. My OE studs were completely mangled and one of them stripped the head requiring a helicoil. If your studs are junk they aren't difficult to replace with something at least newer, if not nicer.