hot interior compartment
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
LOL, welcome to the world of C3's
Do a search in here, there are a LOT of threads on this.
Some fixes:
If your car does not have a hot water cutoff valve, install one, it goes on the heater hose coming from the intake manifold, install it close to the firewall
Wrap the exhaust from the manifold back past the cockpit
Install good sound/thermal insulation under the carpet
Make sure all the firewall holes are closed up
make sure the vent duct doors seal
Do a search in here, there are a LOT of threads on this.
Some fixes:
If your car does not have a hot water cutoff valve, install one, it goes on the heater hose coming from the intake manifold, install it close to the firewall
Wrap the exhaust from the manifold back past the cockpit
Install good sound/thermal insulation under the carpet
Make sure all the firewall holes are closed up
make sure the vent duct doors seal
Drifting
Joined: Mar 2005
Posts: 1,806
Likes: 3
From: Burlington WI
Greetings from Burlington, WI
Originally Posted by jrl1973vette
hey everyone my feet get very hot on the floor boards any one have any ideas to this its almost to the point were it gets almost to hot to drive 
Pro
Joined: Mar 2005
Posts: 683
Likes: 4
Originally Posted by jrl1973vette
hey everyone my feet get very hot on the floor boards any one have any ideas to this its almost to the point were it gets almost to hot to drive
Good Luck
Stedve
Racer
Joined: Sep 2005
Posts: 407
Likes: 0
From: Fort Washington PA
Originally Posted by Easy Mike
It's called "Fish Feet." C3s are well known for being warm inside, Astro-Ventilation not withstanding.
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Intermediate
Joined: Jul 2006
Posts: 41
Likes: 0
From: Manakau City Auckland
Hot feet
Stedve,
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Originally Posted by Tony S
Stedve,
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
You DEFINATELY want all the insulation you can get onder there. If you have that much apart you may want to think about a layer of Nuprene glued to the bottom, good stuff, a thin version of wetsuit material
Instructor
Joined: Dec 2005
Posts: 188
Likes: 20
From: Victoria Texas
I had this problem on my 77. To find the problem, I realized the weathre stripping right in front of the windshield wiper area wasn't being contacted by the hood when it was down. To test my theory that this was where the problem was coming from, I laid a towel all the way across that area and closed the hood. No more heat in the floorboard. So I got to looking at my hood latches, and realized that there were several spacers under them. My hood didn't close that great, so I took out a couple of the spacers. Guess what? Now the hood lines up better and there is no more heat at all in the cockpit.
Pro
Joined: Mar 2005
Posts: 683
Likes: 4
Originally Posted by Tony S
Stedve,
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
Thanks for the advice, I was about to lower my body back down and was not going to bother with all the heat shields. This forum saved me a lot of problems by the sound of it
Thanks Gents from down under
TonyS
Good Luck
Steve
Intermediate
Joined: Jul 2006
Posts: 41
Likes: 0
From: Manakau City Auckland
Originally Posted by SIXFOOTER
Hey Tony;
You DEFINATELY want all the insulation you can get onder there. If you have that much apart you may want to think about a layer of Nuprene glued to the bottom, good stuff, a thin version of wetsuit material
You DEFINATELY want all the insulation you can get onder there. If you have that much apart you may want to think about a layer of Nuprene glued to the bottom, good stuff, a thin version of wetsuit material
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Insulation and Vent Flap Seal Repair
I just installed the Reflectix insulation under my carpeting (firewall surface back to rear compartment). I'm sure that alone did me a lot of good. BUT....while I was at it, I checked all the dash ducting and found that the seal on the main inlet duct (right front kickpanel) was totally shot! And being "cheap", I removed it and re-sealed it myself.
I live in Phoenix and in the summer, my car has never been comfortable inside...even with the A/C on high. Well, between the duct flap rebuild and the insulation, the cabin is now cool when it's 110 outside!
Happy days for one C3 owner! 
I live in Phoenix and in the summer, my car has never been comfortable inside...even with the A/C on high. Well, between the duct flap rebuild and the insulation, the cabin is now cool when it's 110 outside!
Happy days for one C3 owner!
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
I believe so. I've discarded the label, but it is the 5/16" thick foil backed roll insulation stuff you can get at Home Depot in the building materials area. For $20 you get a roll 4 feet wide by 25 feet long; it would do the complete car, if you wanted to do the storage area also. I made sure that the tranny tunnel and as much of the interior firewall that I could reach was covered. It has made a world of difference in the interior temp. But, as I mentioned above, the damper door was leaking engine heat also.
Le Mans Master
Joined: Apr 2001
Posts: 5,436
Likes: 1,253
From: Sarver Pa
2021 C1 of the Year Finalist - Modified
Reflective barrier insulation !!! Fantastic stuff. Cheap and light. Reflectix is one brand, there are others. I used it for the ceiling in my work shop, Now it's warmer in the winter and much cooler in the summer. I WILL put it under the carpet in my Vettes (as soon as I get a chance). It also dampens noise.
Safety Car
Joined: Jun 2002
Posts: 4,757
Likes: 2,506
From: Buckeye, AZ
St. Jude Donor '12-'13
I had the same problem on my '78, but I can say it is cured!!!!! Upon suggestion here in the forum I went over to Menard's and bought a 24" roll of foil faced insulation, I don't remember the name (maybe Reflectix), but it comes in a box in varying widths. It is foil faced on both sides with kind of a bubble wrap type stuff in the middle. When replacing my carpet I put it in in place of the jute, both front and back. I did it up the side of the trans tunnel. I taped all seams with aluminum tape. This stuff molds wonderfully to most all curves. Where my floors and trans tunnel were always hot, I now feel no heat at all. It was noticable enough that my girlfriend commented on how much cooler it was. My AC was out and it was still comfortable in the car with no noticeable heat coming from any floor surface. Another added benefit was some sound deadening.
