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Solenoid brake line lock traction control


BlackBoot
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Has anyone used brake line lock, roll holder ect. Valves used to hold drag cars brakes electronicaly, to control traction? Like the cable system but much easier.

Here is where I developed the idea from

 

http://www.ultimatesubaru.org/forum/showthread.php?p=1119812#post1119812

 

And a link to the devices

 

http://www.jegs.com/c/Line-Lock-Roll-Control-Kits-Components/10159/10002/-1?sendroicid=bbef8492-2d00-41d6-b158-38db0de2603c&sendroiad=1769719539&sendroikwd=Line+Lock&gclid=CKCavaOp-bACFQxshwodNEi_jg

 

Have one valve for each wheel, wired to a central console. Leaves the ebrake system stock so that is safe, and the valves are used in racing, so i'm sure they will work fine, tough enough?

Would this work? Cost vs. reliability? Vs. other options like LSD?

Stop that spinning wheel at the touch of a button and a pump of the brake pedal.

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Would the pressure not be set at the point the lock was engaged?

Applying just enough pressure at the pedal to stop the wheel, and then engage the lock?

I think that the valves only hold the pressure back at the brake and keep it from returning to the master cylinder, so if it is engaged while no pressure is applied it Would not lock, or under light pressure it would drag at the wheel?

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I get the advantages of the cable system, but seems complex, time intensive and costly for my low cost off road beater.

 

The finesse difference here being the control and force is applied at the hand lever in one device in the cable,

 

or at the foot pedal and separate switch requires more hand foot coordination in my solenoid valve idea.

 

For occasional tight spots, it would be nice to just push a button related to the spinning wheel and pump the brake to the desired pressure, then disengage with another push, or optionally timed for convinience and or safety.

 

Also the stock mechanical ebrake safety requirement is not comprimised

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Cable brakes are very innefecient, and sometimes that is a good thing.

 

The cable is poor at transmitting force so it is self limiting, this is why mechanical brakes (aside from the maint nightmare) went away. However for LSD action it is ideal. You have to really work at the handle to stop the car, but you can slow it. So once the spinning wheel hooks up with the ground, the inertia of the moving car will overcome that one wheel, you feel it and all is go. You are also working on just one wheel.

 

With a line lock type setup you have no feed back. Since assuming the car is stuck for some reason, you can not tell what defines too much or too little brake pedal pressure. Normally you would use the rate of deceleration of the car to judge brake pedal input. Odds are there will be too much pressure so once the wheel in question hooks up with the ground, it will be dragging. Sometimes that split second is enough to just get the car stuck again.

 

Granted modern technology does this, but it also usses brake pressure transducers and other complex inputs to decide how much brake pressure to apply to the wheel.

 

You can do the exact same thing just by using your brake pedal. It takes very little pressure to stop a wheel that is spinning with no traction using the pedal.

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I just need something for when I'm on a badly washed out trail, with oppset corners hanging in air spinning, instead of coasting backwards down and trying another run at it.

Or getting high centered on compacted snow, cause I got no lift, yet..

Just need to transfer power to the other wheel for a moment, just to get rolling.

I had suggested having a timed switch to engage the individual wheel lock momentarily to reduce the safety issue that dragging could cause and forgetting it on and damage related to that.

It won't be that critical if the locked wheel drags a bit, if it gets me out in tight spots. I never intended this idea to be used in any other situation, like on road or at any speed, not meant as a replacement for LSD or anything else but an alternative for a specific use.

Cheap simple push button manually selective brake lock.

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I wouldnt go with any sort of timer circuit, just a simple on-off would do. I would however highly recomend a telltail light(s) in your view of vision along with a master on/off switch to disarm the circuit incase someone else gets behond the wheel, and god knows that never ever happens.

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Master saftey switch and indicator lights, absolutely.

I wonder if there valves are available with pressure settings or of some other valve or combo that could do this.

This is somewhat just like a set of selectable hill holders for each brake line.

Where to install the valves? Up front, or at each wheel? Would it be possible to swap them in place of the hill holder valve?

 

If I can source the parts cheap enough, I'd like to try it out, just the rear at first, then maybe the front later if sucsessful or required.

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There are valves that do everything for any combination of features, but they are not cheap.

Grainger

McMaster Carr

Parker

 

Just a few sources. The valves have to be compatable with brake fluid AND handle a possible max 2000 PSI in a panic stop situation.

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I will probably use a pair of those on my Brat if the r160 locker doesn't come through by then. I've already got a front LSD, which will help in the more delicate situations. But when a wheel is completely off the ground, lock it with a line lock, and proceed.

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I've also learned that hot rodders have retrofit ABS and traction control, into early model vehicles.

It would be quite simple to get an ABS unit from the wrecker, and control the solenoids directly without a computer controller.

The abs pump would also alow push button wheel lock without pushing the brake pedal.

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Best combination of ideas would be to have a remote line locker for each wheel, and a row of corresponding switches on the dash. However, instead of locking the brakes ON, you lock the opposite ones OFF, so that then you use your existing brake pedal to give it just as much grab as you need.

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Locking brakes off also, cool.

 

So where to place the valves, can they be put into the joint between the steel lines and the rubberlines near each wheel?

Or can they be under the hood? Are all 4 lines accesable under the hood?

Fittings or adaptor types and size?

 

So at each wheel if sufficiently placed and protected? Or under the hood?

 

For the switches I'd like; lock On, lock Off and momentary 5 to 10 second on or off.

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I like the one about using the line locker to cut off a brake instead of holding one,however if you do this, i REALLY REALLY recomend a momentary switch of some kind, otherwise i can see the potential for a world of hurt, OR a timed relay which works holds for max a few seconds. Personally I would put it under the hood.

 

Are we talking two or four?

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Yeah, you could do the two front ones under the hood after they split, but the rears would have to be done in back. Unless you wanna run individual brake hardlines for both rear wheels and have them branch in front. But this stuff is electrical, so it would mean just running some more wires, no big deal. I just wish I had $160 to blow on experimenting with these solenoids.

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