ok so i was at work discussing brake upgrade options for my car. Being manual i didnt find much but then my co-worker thought about a line lock for the brake lines. Has anyone done this before? Or attempted so i know if its worth looking into?

This has been discussed before. For meeting DOT requirements of an E-brake, a line lock will not work. It may physically work for your application, but do so at your own risk. I am sure others will chime in and explain it more in depth.

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--Jess

'86SE
'87GT
"If you expect the unexpected, was it really even UNexpected in the first place?"

[This message has been edited by jlhuber (edited 07-04-2012).]

That's correct... most if not all jurisdictions legally require an emergency/parking brake system that is hydraulically independent of the main braking system. A line lock needs your main hydraulics to work so if there were problems with the master cylinder, rear lines, or either of the rear caliper pistons, it would be useless. Before ignoring the legal considerations and doing it anyway, you should also consider the liability issues as well. If you're involved in an accident, upon discovery of a line lock as the sole emergency braking system, your insurance company would likely leave you high and dry to settle any accident claims on your own.

Plus line lock are for temporary use only...
They have a nasty habit of leaking down pressure over time and even causing actual leaks too... Hydro brakes are not made for constant pressure.

Example: Parked on a hill and only use line lock? Car is likely to be at bottom or crash into something, or worse, someone when you come back.

Removing parking brakes is illegal for street use. Local laws/inspections doesn't matter. State DOT is least of problem in an accident. DA can charge you and Lawyers will sue for illegal mods.

FMVSS says Parking Brake = Mechanical Brakes

quote S5.2 Parking brake system. Each vehicle with a GVWR of 10,000 lbs. or less and each school bus with a GVWR greater than 10,000 lbs., shall be manufactured with a parking brake system of a friction type with a solely mechanical means to retain engagement...

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Plus an emergency brake is just what it says....for an emergency. If you main brakes fail you can still stop the car by pulling the e-brake. It's not very powerful but better than nothing.

Whats a line lock?

My parking brake was missing when I got the car. Someone cut the cable. I don't know how much other stuff is missing.

"a soley mechanical means to retain engagement" doesn't rule out a hydraulic system to apply pressure. All that's needed is a ratcheting system on the ebrake lever. Usually a ratchet will release if it can't make the next click. As long as the ratchet is at the calipers you wouldn't be depending on the hydraulics to "retain engagement." A couple slave cylinders and the handle and 'master cylinder' might not be much more than the cables and the trouble of keeping them working.

quote Originally posted by Stainless1911: Whats a line lock?

A line lock is an independent valve that you can close once you've pressurized the brakes. The line lock holds the hydraulic pressure on the rear brakes as though you hadn't taken your foot off the pedal.

Thanks.

in that case, as has been pointed out, I don't think its a good E-brake idea.