Heat Insulation

[ABinAUS]

Interested in other members views on the best way to insulate the interior against heat .. there are a range of products in the market and trying to work out the best approach.  Any thoughts appreciated.

[Scott]

From what I've read, the biggest source of heat in the cabin is holes in the firewall that let hot air straight in from the engine bay.  That's probably the place to start before you start spending money.

[RHT]

For my 78, I did the floor insulation when I replaced the carpet which helped but there were 2 other changes that made a difference to the cabin heat. The first was installing a tap in the coolant lines to the heater core. This prevented any heated water entering the heating system. The second was ensuring the hood sealed the wiper area to prevent heat from the engine bay entering the cabin. My hood did not seal and when I replaced the seal and adjusted the latching system - the change was significant. I agree with Scott that sealing the firewall hoses is also a must.
Hope this helps.

Regards
Robert

[VETTENUT]

Somewhere in the tech sections of this forum you will find previous discussions including types and maybe brands of underfloor insulation.
You do not state which generation of 'Vette you have, but the quickest way to cool the cabin of a C4 is to remove the two pre-cats just under the firewall and install one highflow cat further down in the tunnel past the merge point of the exhaust pipes.

[ABinAUS]

sorry guys, I have a C3 in parts at the moment ;)

[Lefty]

I agree wit vets it the cabin temp in my c3 was high until I by passed the heater, now it improved. Haven't worked out why vets need a heater as the heat from the motor keeps it warm inside in winter

Cheers lefty

[sirfixalot]

The main  source of heat is where the heater pipes go up under AC into cabin there is a cavity about 2 " x 1" which lets hot air in. Hot wire fan motor on high & check for leaks into engine bay. If car is LHD there is a small strip of foam which isolates the fan duct area from the area where pipes for heater come into cab. This will allow heat to rise up pipes & then leak into air duct into cab. You can block off where pipes go into cab with high density foam will help, to fix properly remove inner & outer heater AC boxes & seal with windscreen sealer. Replace the internal strip of foam & re- assemble.Sandwich foam between inner & outer boxes & firewall

[ABinAUS]

thx