heater control valve
Thread Starter
Burning Brakes
Joined: Apr 2014
Posts: 829
Likes: 192
heater control valve
This question is LT1 specific but the LT1 in question is not in a Corvette, but instead a 79 Malibu wagon.
I don't have a heater control valve from the donor 94 Z28. I either sold it, tossed it or there wasn't one to begin with, so sorry I don't know that.
Anyway, I want to install a vacuum controlled heater control valve to stop the flow of hot coolant through the heater core during summer months. Will doing so cause any problems with the otherwise intact LT1 cooling system? I just want to make sure since it's a different type of cooling system when compared to the older SBC engines.
Thanks for entertaining my semi non Corvette related question here.
I don't have a heater control valve from the donor 94 Z28. I either sold it, tossed it or there wasn't one to begin with, so sorry I don't know that.
Anyway, I want to install a vacuum controlled heater control valve to stop the flow of hot coolant through the heater core during summer months. Will doing so cause any problems with the otherwise intact LT1 cooling system? I just want to make sure since it's a different type of cooling system when compared to the older SBC engines.
Thanks for entertaining my semi non Corvette related question here.
Safety Car
Joined: Mar 2017
Posts: 4,197
Likes: 1,321
From: LeClaire Iowa
In a corvette you will stop water flow through the intake but that won't make any difference. I don't have a problem with the water flowing all the time. Do you have a problem you are trying to solve? Dan
Thread Starter
Burning Brakes
Joined: Apr 2014
Posts: 829
Likes: 192
I did not realize that the heater core coolant flow might be different in various LT1 setups. Can it be? The LT1 im working on in this instance is from a 94 Z28 and its being swapped in to a 79 Malibu. I want heat available in the car for colder weather but I would like to prevent hot coolant flowing through the heater core in the summer. So, my idea is installing a control valve in the heater hose that stops the coolant flow through the core. I just want to be sure I dont cause any hot spots in the engine by blocking flow through the heater core.
Safety Car
Joined: Mar 2003
Posts: 3,583
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
C4 of Year Finalist (stock) 2019
Although not an LT1, I installed one in an 80 Z28 I restored. I wanted hot water cut off from the heater core for maximum cooling when the AC was on. For vacuum, I tapped into the inside air vacuum solenoid so it only activated and cut off flow to the HC when I turned the a/c on MAX. Worked like a charm and I never had any engine temp issues or "hot spots", and my a/c was always ice cold.
Here's the one I installed ---->
Here's the one I installed ---->
