grumpy73

With my 73 when I am driving it seems to generate a lot of heat. The heater door is closed. Do the C3s generate a lot of cabin heat from the exhaust?

7T1vette

Yes. But there are several common sources of unwanted cabin heat: unshielded exhaust heat; disintegrated jute insulation under carpet; bad seal on right-side kickpanel vent door; missing or collapsed rear hood seal; etc, etc.

There are inexpensive pamphlets that list all of the usual heat sources and how to address them. Just be aware that when these cars were new, they had little problem keeping the engine cool AND the passengers cool. Eliminate/minimize the sources of heat and you will ride much cooler.

ronarndt

I have the entire floor and firewall lined with aluminized stick-on insulation and even with the top down on my 68 convert there is still a lot of heat transferred from the engine and exhaust to the cabin of the car.

derekderek

Put a valve on a heater hose. Hell, as much as you use it, take heater out and throw it away. Then fill the space with a bag of ice... JK.

7T1vette

The rear hood seal and the right-side kick panel door seal are two 'big ticket' items when it comes to heat. The hood seal gets compressed (or missing) after some years and the engine compartment heat flows out the [unsealed] gap at the rear of the hood and directly into the cabin air intake (cowl area). It then flows through that right kick panel door, even if it supposed to be closed, because that seal has long worn down.

VOILA' engine heat in the cabin!!

CanadaGrant

I had never thought of this before but it's a really good idea. The area at the bottom of the windshield is a high pressure area and without that rear hood seal hot air is forced out behind the hood and down into the vents.
I found the biggest change in cabin temp was by installing a shutoff valve in the heater core inlet hose. The heater core is inside the car so keeping the core cool is a must no matter how good all the seals are.

Tim Ware

I had the same problem with my 71-454 until I discovered that the trans. tunnel insulation pad & the foam collar heat shield ( see Corvette America 2018 cat. page 148 ) were not replaced when the car was restored. I could feel the heat poring through the shifter. Now.. no more heat problems. The collar is what seals engine heat away from the interior.