Reducing Cabin / Transmission Tunnel Temperature - Thermo-Tec Heat Shield on Exhaust

[Sean240Z]

Recently, prior to installing Honda S2000 seats into my 240Z, I stripped out my interior to install B-Quiet sound deadening and new carpet under pad. When I pulled back the transmission tunnel vinyl I was surprised to find that the original factory sound deadening tar pad had actually blistered from the heat generated by my exhaust system (the specs on my of my exhaust system can be reviewed here, http://www.classiczcars.com/forums/help-me/12474-header-problem.html, post #18). I knew that on long trips, the transmission tunnel used to get very warm, but I had no idea the transmission tunnel got that hot!

I believe the culprit was the Dynomax Bullet Race Muffler (WLK-24236) that is tucked up inside the transmission tunnel, ~1" from transmission tunnel at its closest point. I considered wrapping the bullet muffler and nearby 2.5" exhaust pipe with header wrap, but have previously had a bad experience wrapping a header (i.e. the header failed after only 4yrs with my car stored for the winters). I did some research and discovered the Thermo-Tec Heat Shields. I decided upon the Thermo-Tec 11634, as the bullet muffler is 4" in diameter (heat shield comes with 4" diameter clamps) and the 3' length would cover the exhaust and bullet muffler from just fwd of the transmission mount to the rear 90^o bend in my exhaust. As my exhaust is 2.5" in diameter, I had to pick-up four smaller pipe clamps at the local auto parts store (i.e. the 3' length comes with seven, 4" diameter clamps). Though the Thermo-Tec heat shield is only 6" wide, I was able to install it so as to shield the driver's side and top of the exhaust system (the drive shaft shields the upper passenger side). Installation was quick and easy.

I like the fact that the Thermo-Tec heat shield stands-off from the exhaust system, so that moisture is not held against the exhaust and air flowing between the exhaust and heat shield will provide cooling. I have not yet driven the car with the Thermo-Tec heat shield installed, however, I'm very optimistic that this install will greatly reduce transmission tunnel heating on long trips.

[Sean240Z]

One year follow-up: Thermo-Tec Heat Shield works extremely well and keeps transmission tunnel temperatures down.

[madkaw]

I used that stuff on my daughters ZXT when I made her 3" exhaust. Expensive but good!