Rear line lock

-
gumper

gumper

Well-Known Member
Joined
Jul 29, 2008
Messages
525
Reaction score
268
Location
Butte, MT
I want to install a rear line lock to operate with my front line lock so I can leave off a button instead of the foot brake. I feel that a button is more consistant than the foot brake. Does anyone know if I need special adapter fittings from the master cylinder, and if the install kits from say Hurst have the fitting I will need?
 
Yes that is correct, in conjunction with my two-step, activated by a push button. It's solely for getting consistant reactions off the bottom bulb. Our pro class is getting real tough to win with worse than a .030 light, and I'm up against trans-brake guys. I hold my own fine, but I'd like a little more of an advantage.
 
I'm not sure how you have it plumbed, but I would imagine you could plumb it to block all four instead of just the front. Although that would mess up locking the front for the water box, if you use it.

You would have to split off the front somehow and tie the rear supply in. I would thing you could get those fittings to do so at a local parts house.

I have been looking at my diagram how I installed mine, and I almost wonder if you would need a second roll control unit to plumb into the back.

Do you have a dual reservoir MC?
 
I think I'd plumb in a second unit for the rears, to the same button,, but have it "switched" so you could turn off the rears when desired..

perhaps separate indicator lites..

Not sure how much hold the rear brakes would have,, you'd have to push really hard to compensate for the proportioning valve,,
 
Grant's nailed it....the back brakes only contribute about 25% of the total braking power of your car, so, even locked, I think they'll have a hard time holding back a decent motor. You can test the theory by putting on your park brake, very hard, then try accelerating...probably won't take much throttle to drive thru the back brakes.
 
Separate line locks both wired to the two step, seen it done and have been trailered by such. Delay box also, was in Super Pro class.
 
I should've said I planned on getting a second unit. The fronts alone won't hold the car back by themselves. I originally planned on using just the front brakes to hold the car from rolling through the lights, but now it's just for the burnout. I'd have to wire two separate switches for just the front locked and front/rear locked.
 
Thats how I did mine, about 30 years ago, two control valves, with a switch so I could pick one or both. with a 2 step and a delay box.. Had to make a 2800 rpm chip for the 2 step, or use a variable resistor. Foot flat on the floor, 2 step holding it to 2800 (brakes won't hold much more)
actually worked really good. Brakes released instantly ( I was concerned about that before hand). 4400 turbo action converter. I had hooked up a brake pressure gauge, but it was too much to watch while staging, plus 2 pushes on the brake pedal buried the 1200 psi gauge.
 
The T-brake is going to go with a new tranny with will also require new axles. I don't have faith in the stock shafts holding up to trans-brake launches. This is just to get me through until I get the money saved up for that big project.
 
I found this in Jegs, #555-63028 $34.99 Hummm,, Got me thinking,,Plumb to all four,,,by pass the prop valve,, might work ? Maybe...
 
That's a nifty piece, but the brake pedal would still be involved in the process of launch.
 
Used the rear line lock this weekend, and it worked perfect. Had to drop my launch rpm from 3000 to 2500, but didn't lose any ET. Ran both the front and rear line locks off the Hurst roll control button, but I'm going to install a Biondo Terminator to fine tune my lights (which ranged from -.003 to .065, average .030).
 
You must log in or register to reply here.
-

Back
Top