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Cockpit Insulation

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I did a bunch of low cost insulation on my Nasty Boy that you can see here: https://forum.britishv8.org/read.php?13,8264 Driving around in 80 degree weather, I'm happy to say the soles of my Piloti driving shoes haven't melted yet! I can't tell you which form of insulation made the most improvement, but here are my guesses. First, take a work lamp and hang it in the engine compartment. Crawl under the dashboard and plug any holes you see where the light shines through. It's usually going to be in a location where wires pass through. Soft caulk insulation that we used to call "Dum Dum" works well for this. I used some DIY "Lizard Skin" that was really inexpensive to make. I don't have any objective data, but the price was low and couldn't hurt. I also used "Reflectix" insulation from the local big box home repair store throughout the interior, which I believe was very helpful. The other thing I believe was helpful was the aluminum covered fiberglass insulation from DEI that I placed under the car above the mufflers.
 
In my BJ8, I used a 1/4" thick aluminized mylar double-faced ("bubble-wrap") insulation material I bought at the local home improvement store. I think it was on a roll 4' wide and cost about $3.00 per yard. Probably cost six bucks to cover all the floors and into the footwells. I put the stuff on both the outside and the inside of the transmission tunnel. The insulation on the floors sits on 30-lb roofing felt which was my effort to duplicate the original tar paper material from the factory.

HealeyRick's recommendation to seal all the air/heat leaks in the firewall first is an excellent one.

After doing all that, my car's cockpit is no hotter than any other car without air conditioning, whereas once the driver's floor melted the heel of my shoe during a long drive.
 
BJ8Healeys said:
In my BJ8, I used a 1/4" thick aluminized mylar double-faced ("bubble-wrap") insulation material I bought at the local home improvement store. I think it was on a roll 4' wide and cost about $3.00 per yard. Probably cost six bucks to cover all the floors and into the footwells. I put the stuff on both the outside and the inside of the transmission tunnel. The insulation on the floors sits on 30-lb roofing felt which was my effort to duplicate the original tar paper material from the factory.
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Sounds like the same "Reflectix" stuff I used. This is what it looks like installed:

IMG_0221.jpg
 
Griz said:
Anybody know of a low cost alternative to Dynamat? Griz
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I purchased Thermo-Tec from Summit Racing. Way cheaper than Dynamat.
(1-roll) #13590 Under the hump
(2-rolls) #14620 All over the inside.
(1) Roll of 1 1/5" metal duct tape from a home improvement store. Used only a few feet.

A couple of big air leaks where the bonnet hinges retract into!! I carefully sealed them but the shroud was off the car when I did that. I also used a Air-Conditioning type of sticky foam tape to seal all the holes on the firewall from inside the car under the dash.
 
Thanks Guys. I found rolls of self adhesive HVAC duct insulation that is foam about 1/4" thick with a heavy foil backing on one side at one of the Big Box stores that I was thinking of installing. But was worried about how it would hold up to the hottest portions of the floorboards. It looks quite like the material in HealeyRick's photo. Guess I'll give it a try. Griz
 
You get what you pay for. For a cool cockpit, Koolmat is tops. Only 1/8" thick and will last forever. Most
NHRA cars use it and you don't get a hotter ride than those guys. Not cheap but why not do it right "once"?
 
HealeyRick said:
Patrick,

My dirty little secret is the Speedpilot isn't hooked up and doesn't work. And the Cobra-style lock-out shifter is fake, too! :jester: But check out Speedpilot auctions online. They go for beaucoup bucks!
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Big $$$$. I know. I've been following the prisec over the years. There's a guy that rebuilds or should I say restores them. The chrome surround plate is rare. I used to Rally several years ago and got to navigate with one of them...nice.
 
I just went through this process a little while back with an early 3000 "Nasty Boy Modified" that I am building. I was analyzing the driver's foot-well situation and what to use. Based upon my experience as a racer - I know what really works. So, I decided to use racer's Aluminized Heat Barrier Cloth. It's 40" wide by 040" thick and sells for $28.79 per foot from Pegasus Auto Racing Supplies. It ain't cheap but it really works. You don't have to do the whole car...only the driver's footwell and under the driver's seat. The passenger doesn't cook unless heat comes through the tunnel.
The more I analyzed the situation though, the more I came to realize that no matter what I did, using the original steel tunnel with that intermediate steel piece, was only going to let heat into the cockpit. Even with using that expensive heat barrier cloth, there are too many gaps for hot air to get into the cockpit. It was not a good design.
So, I decided to use a BJ8 fiberglass tunnel. It is a much better design that totally eliminates that cheesy intermediate piece. Fortunately, I already had an extra fiberglass tunnel, so I bought a Kilmartin tunnel trim kit from British Car Specialists to convert the early 3000 to accept the one-piece BJ8 fiberglass tunnel. Problem solved!
 
That looks very much like what I used, but my stuff didn't have a name. Just a generic roll of insulation.
 
I also recommend Koolmat. I have had it in for over two years and although pricey it is certainly worth the cool cockpit in the South Carolina summer.
 
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