Cooler Footwells
Thread Starter
Drifting
Joined: Oct 2010
Posts: 1,972
Likes: 6
From: Chester Virginia
Cooler Footwells
I followed several threads experience and put a 5/8" brass on/off ball valve inline on the input to the heater core Friday and hose clamped it down. I shortened the handle but tested it for pressure at engine temp yesterday and gave it a ride today with the water shut off to the heater core.
Much cooler footwells and noticeably so. I didn't bother with the return line because you get 90% of the benefit from stopping the flow. Eventually, if you drive the car long enough and stop you'll still get some radiant heat into the footwells but it appears to be from the engine compartment, not from the heater core. I don't know if there is Dynamat under my carpet or not. I'd guess not but that would help i'm sure.
Still, it's much better than it was and i'll leave it off for the summer now.
Lance
Much cooler footwells and noticeably so. I didn't bother with the return line because you get 90% of the benefit from stopping the flow. Eventually, if you drive the car long enough and stop you'll still get some radiant heat into the footwells but it appears to be from the engine compartment, not from the heater core. I don't know if there is Dynamat under my carpet or not. I'd guess not but that would help i'm sure.
Still, it's much better than it was and i'll leave it off for the summer now.
Lance
Last edited by LancePearson; Apr 10, 2011 at 02:58 PM.
Thread Starter
Drifting
Joined: Oct 2010
Posts: 1,972
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From: Chester Virginia
foam collar
Who did you buy it from and what is it made of? Has to be non flammable I'd think.
Thanks.
Lance
Burning Brakes
Joined: Aug 2005
Posts: 801
Likes: 1
One of them is a foam collar and the other one is a shield that gose above the tranny.I haven't installed that one yet due to transmission removal to get it in.just putting in the foam collar helped a whole lot.I have a heater shut off valve that came with the vintageair kit I bought that takes care of the heater core heating up.
Thread Starter
Drifting
Joined: Oct 2010
Posts: 1,972
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From: Chester Virginia
When the foam comes I'll put it on the ramps or jack stands and look carefully under there. I don't like taking the interior trim off the tunnel so will put it in if I can glue it in place above from below. Whoever designed the Vette's interior really didn't design it with the idea that it would be taken out and put back in more than once or twice in it's life in my humble opinion.
I'll have the part in a week and will stick it in in a little while. I have the 3m high temp spray adhesive already from putting in the modern aerospace hood foam liner and getting rid of the cheesy looking fiberglass. Why didn't Corvette in those days give a thought to how the inside of the engine compartment looked? We all sure do. those weren't things which cost much money either though nowadays we have some more sophisticted products than they did in the 60's and 70's. Thanks for the suggestion. Between this and the hot water valve already installed that's all I'll do. You do need the heat in spring and fall and winter here when you drive around with your t tops stored on the garage shelf in their naughahyde bags.
Lance
I'll have the part in a week and will stick it in in a little while. I have the 3m high temp spray adhesive already from putting in the modern aerospace hood foam liner and getting rid of the cheesy looking fiberglass. Why didn't Corvette in those days give a thought to how the inside of the engine compartment looked? We all sure do. those weren't things which cost much money either though nowadays we have some more sophisticted products than they did in the 60's and 70's. Thanks for the suggestion. Between this and the hot water valve already installed that's all I'll do. You do need the heat in spring and fall and winter here when you drive around with your t tops stored on the garage shelf in their naughahyde bags.
Lance
Burning Brakes
Joined: Apr 2009
Posts: 807
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From: VIRGINIA BEACH VIRGINIA
To put the foam collar in, do you have to drop the transmission or can you just shove it down in there? Just wondering, I may get one but not if I have to drop the tranny to do it.
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Le Mans Master
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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The trany blanket can be cut down the middle, installed and taped closed, or pull the transmission. I did mine when I changed the engine.
Lance, I had another 74 back in 77 and I never cleaned the engine. It's different today, we like to show off the shiny stuff under the hood.
Drifting
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I got a vacuum controlled water shutoff valve from Chevrolet that was OEM on an earlier year car. I got the vacuum shutoff switch that was used for the windsheild wiper cover on the 68-72 cars and mounted it under the steering column. Ran an extra vacuum line to it and then to the water valve. Only an NCRS judge would know the difference.
Thread Starter
Drifting
Joined: Oct 2010
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From: Chester Virginia
The AIM shows a foam block glued to the tranny....now to look and see what I have because heat does come into the tunnel and when i get a chance I'll put the new one in as noted. valve helped a lot but this should do more as I suspect there is no blocking left at this stage. Thanks again for all the help.
Thread Starter
Drifting
Joined: Oct 2010
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From: Chester Virginia
Melting Slicks
Joined: Mar 2008
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From: Austin Tx
The 'air dam' is the little black spoiler looking thing bolted to the very front bottom fiberglass. It redirects air up towards the radiator. I think a lot of people in the past have removed these because they tend to get dinged up pretty good, and look bad. But they do play a big role in keeping the engine cool at highway speeds.
Melting Slicks
Joined: Mar 2008
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From: Austin Tx
I got a vacuum controlled water shutoff valve from Chevrolet that was OEM on an earlier year car. I got the vacuum shutoff switch that was used for the windsheild wiper cover on the 68-72 cars and mounted it under the steering column. Ran an extra vacuum line to it and then to the water valve. Only an NCRS judge would know the difference.
One thing I did different is that I tied the vacuum source into the AC/Heater control module. I noticed that in the AIM it showed one of the control lines from the controller as having vacuum with the system either off, or with the AC on. I tee'd my vacuum source for the bypass into this vacuum line. So now my heater core is automatically bypassed with the 4 seasons system off, or with the AC on.
Thread Starter
Drifting
Joined: Oct 2010
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From: Chester Virginia
Thanks, Mashman...got it. Mine is in place but I did check the front bottom of the radiator for trash too. I run a 180 degree thermostat which I like better. Have the foam to install in the tunnel next time car is up. the factory one on the bell housing is glued in place on my...can see from open hood into engine compartment.
lance
lance
Le Mans Master
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From: mount holly NC
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Keeping Cool!
There is a lower shift boot, if it's bad a lot of heat gets into the cockpit. If your going to do the foam and the blanket now is a good time to check that.
Thread Starter
Drifting
Joined: Oct 2010
Posts: 1,972
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From: Chester Virginia
done
Right now I'm not messing with anything since the car is ready for the track day in three weeks from today.
Lance
Burning Brakes
Joined: Sep 2004
Posts: 1,167
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From: Ft.Worth Texas
Wrap your exhaust pipes. If you have headers start where they end and wrap all the way back to the muflers. If you don't have headers but plan on getting some, get the ceremic coated ones. They will really help get that heat out the back.