Insulating the Cockpit

As I work on my '69 GT restoration, and my plans are to install the Moss AC kit, I understand that when you close up a GT, it gets too hot in the cockpit for the AC to even keep up with. I was advised to do one of two things (or both). The first suggestion is to completely insulate the cockpit all around with something like this product, Kool Mat: http://www.koolmat.com/british.shtml

The other idea is to use a ceramic coating named LizardSkin: http://www.lizardskin.com/

Both of these solutions are a bit pricy, upwards of $300 to do a car. I wonder if anybody on the board here has experience with either of these products and what your opinions and comments might be.

crack the rear swing-out windows.

those things work great!

I'm just about to receive my first MGB-GT from Washington state and I've already got big plans to maximize it's ventilation, quiteness, and cooling. First off I'm going to put in the NOS Wabasto sunroof I just procured off off evilBay. That should help make a huge difference in ventilation. Then, next spring I plan to install a Moss A/C kit to get ready for the ever-scorching Texas summers we have. I'm waiting until then so I can get the kit that works with the Moss supercharger as I want to install that little gem too! But in the spring and fall I figure that the combonation of the windows, vent windows, and sunroof will provide all the ventilation I need in mild weather. I also plan to insulate the cockpit with Damplifier Second Skin, as I did in my roadster, to insulate the cockpit from the heat. I figure that I'll end up with a very comfortable, quite interior in my GT. Good luck with yours!

Shawn Escue

I have a 70 GT and it gets pretty hot.

I don't know if I would go as far as "insulating the entire cockpit." Even modern cars aren't "insulated" in the same way as say a house. Theres lots of trim and sound-deadening but not much in the way of serious insulation.

The main sources of heat in a GT from my experience:

Transmission Tunnel (this has some factory heat shielding at least in my 70)
Drivers floor from the exhaust (just the carpet in a stock car)
Fire wall (hot air blown back from the engine compartment)
Radiant heat from the road up into the floor
Radiant head from the sun on the roof
Heat from the sun through the windows

If I were to run AC (I would if I could afford it), I would use the tinted GT windshield from VB, tint the back and side windows, Put heavy insulation on the floor and trans tunnel. And the most important thing would be radiant head shielding in the roof between the headliner and the steel of the roof. I use this cheap, mylar-bubble wrap stuff from home depot. I glue it to the roof and it works great. I don't get that "hotter than" hell parking lot scenario any more its actually quite amazing.

I wouldn't get worked up about getting insulation in every spot, just the floor and the tranny tunnel is where the heat comes from.

Now the only problem your going to have to deal with is how your going to stay warm in the winter!

I used a generic fiber/mylar reflectant insulation in my GT floor. Its kinda looked like carpet padding with a silver mylar layer glued to one side. It couldn't have cost more than $40

Window tint works very well. I also leave the rear vent windows open all summer. Literally, I don't think I closed them at all from April until just a couple weeks ago.

Another trick that works really well for any car is to use a sunshade on the outside of the windshield. Tucked under the wipers at the bottom edge and with elastic straps going in the windows at the top edge.

Most people who insulate only run their insulation up from the floor little higher than the tops of firewall carpet. Altho most of the serious heating does come from the tranny tunnel and under the LH floor (for obvious reasons), it is apparently not so obvious that once the firewall gets heated up from engine compartment heat, it too acts as a rather serious radiator of that heat into the cockpit.

Noting this years ago with my MGA, an even hotter cockpit car, I used some of the "space age" reflective insulation commonly available for cars and hot water heaters (a 1/2" thick mat of shredded and bonded felt, bonded to a tough reinforced reflective mylar film). I covered the floor and the trans tunnel, but also ran it up the full surface of the firewall, covering both vertical sections (like our cars have) and the underside of the "shelf" portion as well. It did not do all that much for noise, but it did make a significant impact on the comfort of the MGA overall, and not just my feet or the seat of my pants. FWIW

I have two BGT's that are Air Conditioned. I insulated under the carpet and over the tunnell.
Works fine for me.
The BGT with the v6. It helps when I stop for gas on a long trip (over 200 miles) to open the hood while refueling. This lets the heat out so it doesn't soak into the firewall. Then it does fine.
I actually have no trouble with the AC unless the temps are over 95. Moast of the summer this year.
Neither car will get a cool inside as a modern car, but both still have air leakes letting in hot outside air. Can't find them all.
Around town they do great.

Steve

I can't say that I have driven mine when it is VERY not (only mid 80's), but with the sunroof tilted up (it is a glass aftermarket one), the two door windows open, and the foot vent open, it actually stays pretty comfortable!

Of course, in traffic it heats up pretty quick. The sunroof definately helps!

Thanks everybody for the input. I may not have been clear in my question but I was referring to how hot the car becomes when driving (especially in a hotter climate like Florida) with all the windows closed and the AC running. I understand the problem areas are the roof, tunnel and floorboards. I think some of the suggestions in this thread are great, such as using the tinted windscreen and also applying tint to the other windows. Of course, this is in addition to adding insulation to the roof and elsewhere.

I may forego the more expensive solutions and follow some of the recommendations here. Thanks!