Line lock installation

[72_671_Demon]

Hello

I'm new to the site and recently purchased a 1972 Demon. The car already had Wilwood disc brakes in the front. I changed the rear drum brakes to Wilwood disc brakes and while I had the brake system disassembled, I decided to install a line-lock and an adjustable proportioning valve.

I found a few good posts about installing a line-lock, but didn't find an answer to the issue I'm having and was hoping someone would havesome ideas. I'm installing the line-lock in the front brake circuit. I want to install it after the pressure differential valve so the warning lamp will still operate correctly. While disconnecting the front brake lines from the pressure differential valve I noticed that the fittings were larger than the rear fitting but all of the lines are 3/16. I assume that was designed that way to prevent someone from installing the valve incorrectly. The pictures attached below show the valve I have and the method of connecting the line lock. The problem I'm have is finding a way to tee the two existing front brake lines to the line lock. The only tees that I could fine are 3/16 or 1/4 flare. The 3/16 tee has the correct flare but the fitting on the line is larger than the threaded hole. The 1/4 tee will accommodate the fitting but the flare does not seat well on the flare in the tee.

I know the obvious answer is to cut off the fittings and replace them with the standard fittings for 3/16 line, but with the headers and torsion bar there is not much room and I'm trying to avoid replacing the right front line since it is routed behind the engine and difficult to get to.

The only other idea I had was to get a second pressure differential valve and remove the stem valve and cut the top half off and drill/tap the hole where the valve was located.

I'm open to any ideas that will make the install easier.

Thanks in advance and any help is appreciated!

 

[TrailBeast]

If you have the line lock already, does it not have multiple ports on it?
Mine (and the one in your picture) have three outlet ports just for that reason.

One line for the front brakes in, plus three output ports.
(one for each of the front brake lines and one for a pressure switch for brakelights when the lock is engaged.)

Also be advized that the ports in the line lock body are not flared compression style, but plain pipe thread (so you will need the fittings to adapt them to flared style fittings, or they won't seal)

BTW, I have mine connected in the front brakes line right next to the master cyl and it has not been a problem of any kind, and made the install go really quick and simple.

Trying to find a pic so you can see how clean it came out.

Note that all I had to do was cut the line and feed it to the lock (one end of it in, and the other end to the out)
The lines are installed in the line lock with 3/16 steel compression unions, and one end of each union has the nut removed and is threaded directly into the lock body.

You will also note that there is no pressure switch or brake light wires visible.
That's because there isn't one. (but I do have brakelights when the lock is active)
I used the power supply side of the lock to send power to the brakelights with a wire section I designed specifically for that purpose.
It allows power to flow to the brakelights, but not from the braklights to the line lock.

Here's both images.

 

[TrailBeast]

I should also tell you that there are other advantages to using the wire instead of a pressure switch for the lights.
One of which is that I can flash my brakelights without touching the pedal at all, because the activation switch for the lock is under my index finger on the shift lever.
A couple of taps on the switch flashes the brakelights. (and I do use it sometimes when stopping in heavy traffic) or when someone is following to close.

I sell the wire preassembled with connectors included, so it is truly a 5 minute install to give a car with a line lock brakelights.

 

[Inertia]

I want to install it after the pressure differential valve so the warning lamp will still operate correctly. /QUOTE]

The lamp always works correctly, it's indicating an imbalance..

May I ask what you are trying to accomplish by not plumbing it between the M/C and the PDSwitch.. You do know the switch is self centering (not like some other brands),, so the lite goes out when the button is released..??

The imbalance lite can be helpful in competitive situations, letting you know that the "tap" you gave to set up for a corner "worked".. and if it wasn't enuff,, to give it another "tap"...

hoping to help

 

[TrailBeast]

I want to install it after the pressure differential valve so the warning lamp will still operate correctly. /QUOTE]

The lamp always works correctly, it's indicating an imbalance..

May I ask what you are trying to accomplish by not plumbing it between the M/C and the PDSwitch.. You do know the switch is self centering (not like some other brands),, so the lite goes out when the button is released..??

The imbalance lite can be helpful in competitive situations, letting you know that the "tap" you gave to set up for a corner "worked".. and if it wasn't enuff,, to give it another "tap"...

hoping to help

There are pretty strong oppinions both ways (before or after the distribution block) and all the manufacturers say specifically to put it after the block.
I think this may be where the OP is coming from.

Still works as one would expect it should between the master and the block.
Also if I remember right, some of the valves don't automatically re center to make the light go off until the brakes are pressed again frimly enought to re center it. (equalize it again)

All this in my own experiences of course, so maybe some differ.

 

[Inertia]

Still works as one would expect it should between the master and the block.
Also if I remember right, some of the valves don't automatically re center to make the light go off until the brakes are pressed again frimly enought to re center it. (equalize it again)

Yeah,, I guess I just shoulda said it's an easier install cuz Mopars self center ,, where-as chebbies and ferds don't.. oh well..lol

 

[TrailBeast]

Yeah,, I guess I just shoulda said it's an easier install cuz Mopars self center ,, where-as chebbies and ferds don't.. oh well..lol

Eh, it's just details

 

[SRT_DSTRHOLC]

You should install it in the rear brakes. Will allow you to lock up front brakes and allow the rear tires to spin freely.

 

[TrailBeast]

You should install it in the rear brakes. Will allow you to lock up front brakes and allow the rear tires to spin freely.

It does exactly the same thing, just one blocks fluid inlet to the brakes (in the rear line) and the other blocks fluid in (when in the front line) Right?
Which also means the orientation of the lock needs to be reversed because most of them allow fluid into the brakes but not back out. (meaning pressing the pedal with the lock engaged allows more fluid to the brakes but not back out) until the lock is released.

Since this is the case, putting it in the rear brakes line would require that it be installed with the flow direction reversed. (so it wouldn't allow fluid into the rears while holding the fronts on)

Sound reasonable?

 

[Mad Dart]

It does exactly the same thing, just one blocks fluid inlet to the brakes (in the rear line) and the other blocks fluid in (when in the front line) Right?
Which also means the orientation of the lock needs to be reversed because most of them allow fluid into the brakes but not back out. (meaning pressing the pedal with the lock engaged allows more fluid to the brakes but not back out) until the lock is released.

Since this is the case, putting it in the rear brakes line would require that it be installed with the flow direction reversed. (so it wouldn't allow fluid into the rears while holding the fronts on)

Sound reasonable?

I have never had any luck holding a car with a line lock in the front brake lines, even after pumping the brakes 10 times before activating the solenoid.. Car would always creep forward.

Mine is not installed reversed & in the rear line after the distribution block and after a wildwood adjustable proportion valve. 4 wheel wildwood disc brakes. I flip a switch and a momentary button on my shifter activates the line lock solenoid. Fluid is locked out of the rear lines before the brake pedal is pressed. After activation pump up the front brakes as hard as you need to in order to hold the car keeping your foot on the pedal. Rear brakes are inactive free wheeling as you do burn out. Let go of brake pedal and button car moves forward & out of the burn out.

 

[TrailBeast]

I have never had any luck holding a car with a line lock in the front brake lines, even after pumping the brakes 10 times before activating the solenoid.. Car would always creep forward.

Mine is not installed reversed & in the rear line after the distribution block and after a wildwood adjustable proportion valve. 4 wheel wildwood disc brakes. I flip a switch and a momentary button on my shifter activates the line lock solenoid. Fluid is locked out of the rear lines before the brake pedal is pressed. After activation pump up the front brakes as hard as you need to in order to hold the car keeping your foot on the pedal. Rear brakes are inactive free wheeling as you do burn out. Let go of brake pedal and button car moves forward & out of the burn out.

Now that is an example like I mentioned.
My lock would allow the fluid to bypass the valve and apply the rear brakes anyway, and release when I released the button.

If pumping up and holding your brakes makes the fronts hold the car, then it should hold the car with the lock in the front line holding the pressure on the fronts.

Hmm, wonder why it doesn't?

 

[Mad Dart]

Now that is an example like I mentioned.
My lock would allow the fluid to bypass the valve and apply the rear brakes anyway, and release when I released the button.

If pumping up and holding your brakes makes the fronts hold the car, then it should hold the car with the lock in the front line holding the pressure on the fronts.

Hmm, wonder why it doesn't?

I believe it has something to do with the factory Distribution block "Bleeding Back to the Rear line inside the Block" Last car I had this problem with was a 70 Swinger. There are SEVERAL different kinds of Distribution blocks. Maybe it is only on a certain block?? I had the line lock right where yours is. Pump it up, hold the line lock, let off brake pedal, start burn out and the car would push right through the braking. The longer you did burn out it got progressively worse.

The not holding the car is a standard problem. I am not the only one this has happened too. This is why a lot of race car guys plumb it into the back & AFTER the Block. You will never have that problem when installed this way. 4spd guys... Well, you better be on your game with some fancy foot work.

I challenge you to go out set your line lock and give it enough throttle to load the car on the front brakes. Hold it there giving it more throttle to just before the car starts to spin. You may be surprises as your car too may push right through the front brakes as well.

 

[TrailBeast]

I believe it has something to do with the factory Distribution block "Bleeding Back to the Rear line inside the Block" Last car I had this problem with was a 70 Swinger. There are SEVERAL different kinds of Distribution blocks. Maybe it is only on a certain block?? I had the line lock right where yours is. Pump it up, hold the line lock, let off brake pedal, start burn out and the car would push right through the braking. The longer you did burn out it got progressively worse.

The not holding the car is a standard problem. I am not the only one this has happened too. This is why a lot of race car guys plumb it into the back & AFTER the Block. You will never have that problem when installed this way. 4spd guys... Well, you better be on your game with some fancy foot work.

I challenge you to go out set your line lock and give it enough throttle to load the car on the front brakes. Hold it there giving it more throttle to just before the car starts to spin. You may be surprises as your car too may push right through the front brakes as well.

No, mine holds solid even at 5000 R's and tire smoke for a half block.
I havn't used it much but I was downtown one night and decided to give it hell and see what happens.

the fancy foot work comment reminds me of a stick car that won't idle without dying coming up to a red light.
Right side of the right foot is throttle, and the left side of the right foot brakes.

Been there a few times over the years.

 

[Mad Dart]

No, mine holds solid even at 5000 R's and tire smoke for a half block.
I havn't used it much but I was downtown one night and decided to give it hell and see what happens.

the fancy foot work comment reminds me of a stick car that won't idle without dying coming up to a red light.
Right side of the right foot is throttle, and the left side of the right foot brakes.

Been there a few times over the years.

If it holds that is good. There may be something going on with a different factory distribution blocks.

I hear you on the fancy foot work. I too have had 4spd cars that did not like to idle. Looked like a paddle boat operator! haaaa

 

[Inertia]

I have installed dozens of line-locs,, always to the front,, and they all held the cars until the car pushed the locked wheels forward, or broke the rear wheels free..

These are every kind of car, from Pro-stock, gassers, S/S, stk, street,, blue oval, bowtie, ricer, euro...

If your front brakes won't hold, it's not the line-loc,, unless it's defective.

But I do understand how your way works too.., your footbrake is the release rather than switch, and manual trans cars are a "challenge",.. lol

 

[TrailBeast]

If it holds that is good. There may be something going on with a different factory distribution blocks.

I hear you on the fancy foot work. I too have had 4spd cars that did not like to idle. Looked like a paddle boat operator! haaaa

It could be just a difference in tire rubber composition also, as I notice the rubber on my tires seems a little hard.
They don't squeel or anything on dry surfaces, and when driving on wet pavement it spins super easy.
With stickier tires it could very well push through.

 

[Mad Dart]

Line lock is not really even needed...... More of a novelty item! Old school POWER Brake works fine letting off the brake as the tires start to smoke..... Of course this is IF you have enough power to actually get the tires spinning! Lol

 

[KosmicKuda]

I installed a Hurst Line-loc in my car a few years ago. I took the distribution/safety switch off and just plumbed a Tee in it's place. The Line-loc went between the MC and Tee, and then one line to each front disc.
I put a Wilwood adjustable valve in the line between the MC and rear brake line. For me, simple is good, less leakage points and less weight.
My red dash light no longer works but so what? It only tells you when you have a leak. With all the plumbing and flaring I had a very small leak that I didn't see but I could feel the pedal go down VERY slowly. I tightened one fitting and it's been good for over 5 years.

 

[qkcuda]

I eliminated the factory junction block on the frame rail altogether, as my car was a drum brake car and I had to get a new proportioning valve for the front disc conversion anyway. I bought the bracket with the proportioning valve and mounted the line lock right below the bracket. You can see the plumbing in this picture. It has been working flawlessly.

 

[Inertia]

Line lock is not really even needed...... More of a novelty item! Old school POWER Brake works fine letting off the brake as the tires start to smoke..... Of course this is IF you have enough power to actually get the tires spinning! Lol

Actually, for decades, my line-loc has become part of my every day driving,, as much as the gas or brake pedal.. I use it at every lite, no more holding the pedal, I use it starting on hills, I've used it to help "park" in certain situations, ;-)

Line-loc is now being introduced in production cars under different names, "roll-control", and "hill assist" are some examples...

And it saves burning up the rear brake shoes doing "brake stands"..lol

hope it helps

 

[Mad Dart]

I eliminated the factory junction block on the frame rail altogether, as my car was a drum brake car and I had to get a new proportioning valve for the front disc conversion anyway. I bought the bracket with the proportioning valve and mounted the line lock right below the bracket. You can see the plumbing in this picture. It has been working flawlessly.

I almost did the same thing. The factory location is a full blown PITA to get to if your engine & Headers are in the car.

 

[72_671_Demon]

Thanks for all of the replies!

May I ask what you are trying to accomplish by not plumbing it between the M/C and the PDSwitch.. You do know the switch is self centering (not like some other brands),, so the lite goes out when the button is released..??

My thought for installing it after the differential valve was to not create an imbalance which would cause the lamp to illuminate. I wasn't sure if this valve would re-center after creating the pressure differential.

You should install it in the rear brakes. Will allow you to lock up front brakes and allow the rear tires to spin freely.

I'm warming up to the idea of installing it in the rear brake circuit. I like the idea of it being the same as a "brake torque" without having a line-lock. In other words, using the brake pedal to control the roll-out.

Since this is the case, putting it in the rear brakes line would require that it be installed with the flow direction reversed. (so it wouldn't allow fluid into the rears while holding the fronts on)

I have the Hurst 174 5000 line-lock. Does anyone know if I need to reverse the lines or will it work per the instructions?

 

[fastoldman]

Haven't installed mine yet, so now I have some confusion as to how I will install mine, which isn't uncommon for me! Thanks alot guys......LOL