I'm in the middle of swapping out my clutch for an FM1 as well as doing the seals and bearings in that area.
I thought it might help with noise/footwell heat if I insulated the trans tunnel. I've heard of people doing this before, so I went to the hardware store and picked up some of
this duct insulation. Its rated for 180 degrees F, which worries me. If I place this up along the driver's side footwell, will the exhaust be able to burn it up? I'm running an RB header in an NB2 which is substantially larger than stock.

 

I am using that or something similar. I picked it up years ago from Lowes. I cleaned the inside of the tunnel as much as I could, then used 3M spray adhesive on the body, then attached the sticky side of the insulation. It has held up reasonably well over the years.

 

Just clean the surface well with some sort of degreaser or brake cleaner and it will be just fine. I have applied the same exact stuff 8 years ago and I've done some really bad things to my car, including running very high EGTS and over 300whp on track and that is still just fine. I would do it again.

 

Well, you could just do it properly and get the DEI Floor and Tunnel Shield. The adhesive is rated to 450F. Given the labor involved to drop the trans, I'd follow the buy once, cry once philosophy. I covered the entire tunnel on the exhaust side with it.
I also wrapped the top half of the exhaust with DEI form-a-shield from the back of the header to the muffler. July race weekends aren't nearly as brutal as they used to be.

 

Or you could do what Godless Commie did in his build thread.

 

I use a DEI PSA backed insulation on the tunnel with HVAC tape sealing the edges. I want to try their Form-A-Barrier (https://designengineering.com/formable-hard-shield/) with an air gap when I swap back to a turbo.