Brake Pressure Switch ?? Need A replacement

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billsdartgt

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With my upgrade now to the Wilwood MC and the Wilwood proportioning valve the stock pressure switch will not work, it is different threads. The Wilwood prop valve comes with a switch to activate your brake lights but I haven't found enough info as to whether it would work as the idiot light, its also a 2 wire instead of a single wire. What switch are others using when going to a different style - I have not anything found here on the site and googling hasn't gotten me anywhere, below is the stock switch, thread on the new prop valve is 1/8"X27 npt - not sure what this even is. Car is a 69 dart GT, original all manual drum brakes, not sure if the stuff in the car is original or not

switch
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crap switch was in

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Most likely the new switch with 2 posts is just a SPST switch. If you were to ground one post and hook the other to the stock wire you would be good to go.

Just reread you post, are you sure the willwood switch is to activate the brake lights?

The idiot light switch in the OEM distribution block works with a piston inside the block that when the pressure on one side is reduced, causes the piston to move to one side making a path to ground to light the idiot light up.
 
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Any pressure associated with the brake system "usually" turns the brake light in the dash on in the event air gets into the system. They don't normally operate the brake lights. Your brake light switch should be mounted down around the brake pedal and should be either a one or two terminal switch, depending on model.
 
Most likely the new switch with 2 posts is just a SPST switch. If you were to ground one post and hook the other to the stock wire you would be good to go.
From what I read this seems like it would work, gonna try it since I don't have anything to lose at this point

Just reread you post, are you sure the wilwood switch is to activate the brake lights?

This is the info from the Wilwood site

The idiot light switch in the OEM distribution block works with a piston inside the block that when the pressure on one side is reduced, causes the piston to move to one side making a path to ground to light the idiot light up.

That is what I read, some of the switches I have seen work this way, even listing the pressure differential

Any pressure associated with the brake system "usually" turns the brake light in the dash on in the event air gets into the system. They don't normally operate the brake lights. Your brake light switch should be mounted down around the brake pedal and should be either a one or two terminal switch, depending on model.

I found the brake switch when undoing my brake pushrod - nice deep scratch on the arm, no confusion on that one.

I figured I can't be the only one who has done the swap, will keep diggin for info,, Thanks for the replies.
 
What you hold in your hand is not a pressure switch nor is it a brake light switch. It is mechanical, operated by the shuttle piston in the prop valve assembly, and really is not necessary except to "plug the hole"

Since you are referring to a non factory assembly, I'd say contact whoever you got that from. I would "suspect" GM is who actually made it
 
Guys, thanks for the replies, my calling this a pressure switch is due to what I found googling only as a reference, I assumed with all the brake swaps and upgrades that someone here on the forum had already been down my path. I can make the Wilwood switch work to trip an idiot light, since I have run into some new experiences with this Mopar figured I would ask for any tips - thanks again
 
so after some more geeking out over this, the Wilwood switch will not work, found some more online data to confirm its operation, there are a few aftermarket switches that seem like they will work which operate from a differential pressure, more research, perhaps I can end up with the answer to the question maybe I should have asked

What brake light warning switch are people using for replacements or after brake swaps?

curiosity didn't kill the cat, it killed the car guy LOL
 
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