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Cabin heat problems

Old Oct 31, 2013 | 11:59 AM
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Default Cabin heat problems

I have a 74 BB with no AC but from what I hear it won't help much to add that feature. The cabin will just get too hot driving for a long period on a hot day with or without it. Pretty much all have the problem small or big block but there are some partial solutions. No real fix as I hear though.?
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Old Oct 31, 2013 | 12:12 PM
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You can put more insulation on the floor pan and firewall, and a coolant cut-off valve on the heater core.. Don't know if that would help (or you've already done it).
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Old Oct 31, 2013 | 12:15 PM
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Sounds like bull to me! My 68 small block will freeze you out!
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Old Oct 31, 2013 | 12:25 PM
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If the car is functioning correctly the factory A/C is more than enough to cool the cabin.
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Old Oct 31, 2013 | 12:29 PM
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I'm not sure what you're asking, but I had a 74 coupe with factory air and was always comfortable.

Slip some Reflectix under your carpets and you'll feel a difference.

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Old Oct 31, 2013 | 12:37 PM
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If your seals in your duct work are not sealing (blend door) it will allow hot air into your ducts. I do not believe that non A/C cars have a hot water shut off valve but you can add one manually inline to eliminate water flowing to your heater core. The there is the hood to cowl seal, is it in place? As Mike said installing heat insulation will help a bunch.
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Old Oct 31, 2013 | 12:40 PM
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Adding AC may help! Alright that's good to hear. Now keeping the engine cool enough with it running becomes a threat but may not be so bad. Thanks
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Old Oct 31, 2013 | 12:45 PM
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Originally Posted by Roco71
If your seals in your duct work are not sealing (blend door) it will allow hot air into your ducts. I do not believe that non A/C cars have a hot water shut off valve but you can add one manually inline to eliminate water flowing to your heater core. The there is the hood to cowl seal, is it in place? As Mike said installing heat insulation will help a bunch.
Yeah I had to remove that for high rise manifold and other custom parts. Ok that could be key to the problem and realize the importance of it now. Thanks
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Old Oct 31, 2013 | 12:49 PM
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Originally Posted by CiCiC3
Yeah I had to remove that for high rise manifold and other custom parts. Ok that could be key to the problem and realize the importance of it now. Thanks
Without that seal hot air is coming from the engine bay into your cowl and right into your fresh air vents. That seal is all of about $8 or less. Major contributor to your problem.
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Old Oct 31, 2013 | 12:55 PM
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Yeah, that would make his car like August in the Southwest alright!
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Old Oct 31, 2013 | 01:13 PM
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Originally Posted by Roco71
Without that seal hot air is coming from the engine bay into your cowl and right into your fresh air vents. That seal is all of about $8 or less. Major contributor to your problem.
That sounds like you hit the nail on the head, I forgot about that detail and that is where most of the heat is coming from the vents. Thanks
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Old Oct 31, 2013 | 01:49 PM
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As it sits now I have no need for a summer BBQer
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