Under Axle Exhaust

Those such as Adam that are running that setup usually also have a full s13 rear subframe conversion which only allows for an under axle setup. I'm running a 3" custom setup over the factory axle with no issues.

That is correct

s13 has the room to run it under as the subframe allows.

z31 just doesnt have the spacing to do so. I have both the MSA and CM exhaust, and the MSA was an easier fit with the assembly. Occasionally MSA will run a sale on the 3" version for $159 for which I picked up my years back. I see it pop up a few times since then. I have not seen their 'non turbo' deal but the piping looks to be nice (questionable muffler).

Other option would be to go with oval or square narrow for clearance under the axle but not sure that would be that much better.

Okay, I gotta ask, do you guys just not have custom exhaust place in the States? There's several places within an hour's drive where I can get a mandrel-bent, manifold/turbo-back single exhaust done for like $200 (more for stainless) if I bring my own muffler (don't need a cat on a pre-89 car here.) Maybe it's because exhausts rust out in 3-4 years here?

Yes, they are everywhere. It just depends on what you are looking for - for nice mandrel pieces performance shops will do a much better job.

For the s13 subframe, I have a fully custom exhaust. I relocated my muffler to where the cat is located (3" in 3" out), where the OEM muffler is located I went with y pipe with dual 2.5" out..

CM and MSA have the hard work figured out with over axle, which will give shops some difficulty, where cost end up evening out between full custom and pre made.

Having had both, I would probably go full custom again.

edit, I do not know why I cannot link in images into my posts

Ooooh, I see. Thanks for the info guys! I had forgotten about the clearance difference when doing the s13 subframe swap. I was wondering how people fit the piping under the oem z31 subframe but it turns out I was just confused… haha.

I have done 3" under the subframe before, on my z which was lowered about 1" it kept hitting everything it was a pain int he ass