This probably isn't a big topic but it might provide some helpful info. I have a '79 U.S. GTB. Being a U.S. car it once had CATs but no more. I had stainless steel bypass pipes made years ago that made a noticeable difference in acceleration and I got rid of a HUGE heat source. As you might be aware, the U.S. cars had a platform on the trunk floor that provided more insulation from the CATs. This took up almost 2" of vertical height within the trunk and really didn't help reduce the heat load. This makes for going anywhere with luggage an issue...especially for the wife's make up which can become a little gooey. Not good. Well, I set out to attempt to remedy this situation and here's what I did. Your results may vary. I took my platform out and put it on the shelf, took up the carpet and put down some new tech foil backed insulation across the trunk floor, and also removed the old insulation on the trunk firewall (in thewide "v" shaped indentation) under the carpet and replaced it with Lynn Manufacturing Universal Baffle Blanket, Superwool, 2100F, 24'' x 20'' x 1/2'', 2255E available thru Amazon, I then covered that with Thermo-Tec 13575 Adhesive Backed Aluminized Heat Barrier, 12" x 24", also from Amazon. I then used spray adhesive to re-attach the carpet. I also wrapped the CAT bypass pipes with DEI Titanium header wrap. and placed a heat barrier over the top of the factory muffler. Results? Florida 90 degree day, car driven about 15 miles, A/C on (yes it works), parked the car with the engine running for about 15 minutes, then drove another 2 miles back home. Checked the trunk and it was still cool inside from being parked in my garage. So perhaps this might be of interest for those who live in the warmer climes, good luck.
Do you think lowering the trunk temp will lower the cabin temp? There is a big old hunk of sand cast Alu in between you and the trunk.
You know, I think if the superwool was used as I did in the trunk on the cabin firewall, I think it would help. But that's a big job. I'll tell you one thing I did was to tint the windows. Not with some dark tint, but 3M Crystalline (specifically for autos with a lifetime warranty) and I did all the windows including the inside of the windshield. It's a virtually clear tint that removes about 90% of the UV rays and boy did it make a difference! I even put it in my BBi and it made a HUGE difference. Although it's "clear" it does have the slightest blue hue to it but it's not really noticeable. There are darker shades but I didn't want to look like some gang banger!
That is one of the many things ( clear Tint) I would of liked to do on mine but there are too many small things to get done that I never do. Im getting a lil bored. September just marked 20 yrs with mine. Ps the cabin firewall is easy to do when the engine is out, Rivets rivets drill drill
I was talking about doing the firewall on the inside. But you're right on the engine out scenario.. I've had my GTB since '93. hey that rhymes!
Actually the fuel tanks need to be moved or removed to get to the rivets. If you have the rear seat out I’m sure some mat could be placed in the seat frame recesses
