Any good overpipe->midpipe solutions?

[Escher]

While doing a transmission drop this past weekend, I ended up having to decapitate one of my overpipe->midpipe studs, something that apparently is some kind of right of passage with these cars.

So I'm upgrading to an aftermarket overpipe, probably an Invidia, as I'm planning on upgrading the whole exhaust down the road anyway.

So first of all, the studs are welded to the overpipe aren't they? On all of the product images, on 86speed and amazon etc, I'm not seeing studs welded.

Second of all, is this heat-cycling-leads-to-decapitated-stud issue just simply unavoidable? Or do aftermarket products handle it better? Is there any solution if not?

Thank you!

[EndlessAzure]

Originally Posted by Escher

While doing a transmission drop this past weekend, I ended up having to decapitate one of my overpipe->midpipe studs, something that apparently is some kind of right of passage with these cars.

So I'm upgrading to an aftermarket overpipe, probably an Invidia, as I'm planning on upgrading the whole exhaust down the road anyway.

So first of all, the studs are welded to the overpipe aren't they? On all of the product images, on 86speed and amazon etc, I'm not seeing studs welded.

Second of all, is this heat-cycling-leads-to-decapitated-stud issue just simply unavoidable? Or do aftermarket products handle it better? Is there any solution if not?

Thank you!

Studs are, by their nature, not welded.


Studs are just bolts without heads. Some have an unthreaded portion near the middle to keep them from continuing to thread through.


Studs just happen to snap in the overpipe/midpipe a lot due to heat cycling, which causes the nut to tighten/bind more-and-more over time. By the time it comes to remove the assembly, the amount of force required to remove the nut causes the stud to just snap instead. You would be surprised how easy it is to actually snap bolts in practice. When this happens and you want to re-use the part, you have to extract/drill-out the broken stud and install a new one.



The best you can do is use anti-seize during assembly, and allow penetrant fluid to soak before disassembly. If it's really stubborn, use a torch.


An alternative is to use a thru bolt + a blind hole instead of a stud + threaded hole. Some systems are like that. You can "retrofit" this onto an existing system (though I'm not sure I would recommend it). You will sacrifice some strength because you need to get a bolt that is smaller than the existing stud hole.

[86MLR]

Spray, don't snap