How hard would it be to add a heater core bypass valve? Iv been wondering this but since I got my ac working yesterday I want it to be as cool as possible. I'm looking more towards the factory setup like on the 90s where it was controller by vacuum

 

You could do that, how is that one controlled? Is there a vacuum switch inside the car?

 

I couldn't tell you honestly. I remember it having two ports on it for coolent lines and a vacuum port in the top that you plugged a hard vacuum line on

 

I was going to do the same thing. Ended up buying a $4 ball valve from lowes, sprayed it black, and put it in the hose. Cheaper and cleaner IMO. Only thing is I have to pop the hood to get the heat if I want it. Takes all of 15 seconds to do though.

 

That's why I like the idea of the stock bypass on the older cars. I think it opened up as you moved the lever to heat

 

I am going to look at the possibility of hooking a choke cable up to it. Not really worried about that right now.

I know some older vehicles had a similiar setup. I know 69 F100s had a manual valve on the heater core that worked off a cable connected to the HVAC controls.

My problem with the factory unit is the extra ports.

 

I'd really like to see a picture of where that ball valve is, and how you did it. it completely cuts off flow to the heater core?

 

Dude, you didn't save the valve and line from your V6? Go to a junkyard and get one. The valve may be junk, however, if you get it from a yard.

(OOPS, just noticed the old post... )

Bit of a misnomer... The bypass valve allows coolant through the core anytime the heat control lever is not in full COLD. Used to have to keep the temp lever in full COLD to keep the heater from burning my feet during the summer (no working temp control door). And yes, it's controlled by a secondary vacuum switch that is actuated by the temp control lever, on the bottom of the control head. That's why the vacuum system has 2 black vac lines, one is vacuum inlet and the other is heat control.

Anyways, the ball valve would be quite simple... Get 2 intake coolant hose ports and one 1/2" ball valve. Put the ports in the valve, put the valve in one of the lines running to the heater core pipe running down the frame rail, and you're done...

 

Digging up bones here.

 

Sitting right beside the valve cover on top of the intake.

Just do what was mentioned in a post or two above, cut one of the lines going to the heater core, insert ball valve. It is really that simple. Put it where you want to put it that you can easily get to it.

 

Something like this?

 

No.

More like this.



Just run the coolant lines cleaner and closer to the crease between the intake and the valve cover. I have the valve roughly above the #4 cylinder.