Just recently purchase my first vette last August. It's a 72 with a 454 automatic. When driving, I get a lot of heat which seems to radiate from the firewall, through the floor heat vents and a small amount thought the middle dash vents. Temp gage shows 185. I've been told by the local Chevy dealer that this is probably normal because of the 454 in such a small space and no room around engine to vent. On hot days it becomes rather uncomfortable. Is this true?

Hi John,

There are many, many threads in this forum that discuss interior heat in the C3s and several possible solutions. Do some more browsing and I'm sure you will find an answer.

The heat issue isn't just with big blocks. You might notice that heat also appears to be coming from the trans tunnel and from under the carpet. That's because it is. The fiberglass floor doesn't insulate well. Originally the trans had an insulating blanket covering it and there was a piece of foam type material on the top to keep heat from the engine bay moving under the floor. Unfortunately, many C3's no longer have these two pieces. Suggest you check under the hood/car. If they're not there (or are in bad shape) consider replacing them. It may not seem like it, but they do make a difference. Also, you could consider putting one of the "space age" insulating blankets under the carpet. Most of the big Vette suppliers sell them. I've done all of the above and the interior is now significantly cooler. (Previously, my wife wouldn't ride in the car if the temperature was over 85 -- and my A/C blows cold!) Hope this helps. Have a good holiday, enjoy your "new" Vette and save the wave!

Mike, thanks for your help. Strange the local Chevy dealer didn't have an answer. Being new at this and not terribly mechanically inclined, where does one go to get work like this done?

If you haven't already, suggest you start by getting catalogues from all the major parts suppliers -- Corvette Central (MI), Mid-America (IL), Zip Products (VA), Eckler's (FL), Corvette America (PA). They all have web sites that allow you to order. At least this way you'll have the correct parts. It's not surprising that a Chevy dealer wasn't very helpful. It seems only a select few dealers have a Corvette specialist and even then, they're not always well versed in the older models. Corvette Fever ran an article in their January 2002 issue called "100+ shops you can trust". They plan on doing it again in the near future. You might be able to find someone in your area that way. Otherwise, you could try high-performance shops close to you. They may not want to do the job, but may be able to provide a name of someone who would. The trans blanket isn't too difficult providing you get the car up on jacks or ramps and don't mind laying on your back for awhile. Just wiggle it back and forth. Shouldn't require any tools other than a pair of scissors. The foam over the top of the trans just kind of pushes into place and holds itself there. The under carpet insulation isn't complicated, it just takes time. If you're considering redoing your interior, that would be a good time as it easily fits under new carpet. Remove the seats and you pretty well have access to everything needed. Also, you may want to get a copy of Hanes and/or Chiltons repair manuals (or both). They have a lot of pictures and good explanations of how to get at things. This way you can decide if you want to tackle a project or get professional help. It also provides insight into the job to help you make sure it gets done correctly and that you get your money's worth if you choose not to do it yourself. Hope this helps.

There are several posts about heat related problems.
You may need to add a manual shut off valve to replace the vacuum actuated valve that provides shut off to the heater core. My vacuum actuated valve would leak by, the manual shut off took care of the problem. Hope this works for you. Only problem is you need to manually open and close the valve when you want heat. For me in Florida, this is not too often.

One word...

DYNAMAT


Worked miracles for my vette.
You need to tear out the interior to lay it down, but the end result IS WORTH IT>

This forum is great! How many of you thought that only you had this ( or that ) problem.

Hey Fla vette... what I have been doing is remove the hose going to the heater and reconnect to the block,because I thot a tap would impede the coolant flo.Where did you put the shut off?
Thanks
Phil

There is a vacuum actuated valve that provides shutoff to the heater core (just follow the heater hoses and you will see it). I removed this valve and inserted a manual shutoff valve in its place and plugged the vacuum line.

Have this problem too, will look to fix tommorrow. Thanks