Exhaust manifold studs vs bolts

[jbranch]

For my rebuild, I bought a performance exhaust system and headers. I think I will ditch the bolts provided to install the headers and use studs instead. I'm going to have to use one stud as it is because one bolt hole was damaged during the removal of the old manifold. I'm hoping that will make disassembly easier later on. Does anyone have any experience with this?

[Tom]

I don't have experience with that motor on particular, but in general studs are better for exhaust manifolds in my opinion because they will put less wear and tear on the threads in the head. Way too easy to cross-thread, strip out, or just wear out aluminum threads with steel bolts when installing and removing with headers in place. You get a more consistent, uniform clamping force with studs also, though that may be of lesser importance on an exhaust header than on, say, a rod cap. On most performance engines, Porsches included, factory engineers will use studs if they can. Sometimes with after market exhausts, the flanges and/or tubes can interfere with the ability to use all studs, so bolts are supplied instead.

https://www.hpacademy.com/technical-art ... -vs-bolts/

[jbranch]

Good point on the aftermarket thing. I'll have to verify no interferences. Thanks