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Discussion Starter #1 (Edited)
This how-to is dedicated to Patrick Olsen. Thanks for keeping me motivated.

THE WHAT

ABS sucks. Pulling fuses is for suckas. Delete it, everything, take it all out and bend your own new lines. Not too much money. Just realize that this is pretty much a one-way modification and your warranty is most certainly VOID if you do it.

THE WHY

I'm with this guy. Also, check out "moral hazard" on Wikipedia. People drive faster and crazier with ABS, thinking it will save them. I drive within my and my car's limits because I know I don't have ABS to rescue me. Sort of counterintuitive but it's true. That said, if you're thinking about doing this and you're under 18 or are doing it on a car you don't take to the track, just don't. If you've never driven without ABS, just don't. Brakes are the most important system in the car and modifying them is dangerous. If you make a mistake and your brakes fail, you might get hurt, hurt someone else or worse.



I personally think non-ABS cars are safer in the right hands and in the right situations for a lot of reasons. ABS also teaches you bad driving habits, i.e. slamming the brakes on instead of threshold braking. It makes the pedal feel weird and rubbery. The Subaru ABS ECU thingee is especially stupid. It freaks out over potholes. There is a large amount of physical wiring and voltage devoted to ABS and a ginormous pump to route it all. And it's heavy (20 lbs hanging right off nose where you really, really don't need that weight, plus a ton of wiring and the computer.) It's unneccessarily complicated. It's always in the way when you're working in the engine bay. Plus those dudes in Initial D from the Tudoh School trained without ABS, so it must be hella tight, right? Haha, seriously, I did set my car up for windy road/canyon/tougue type stuff and I did it mostly for the weight, because I'm anorexic like that. Some people just don't like ABS. Deal, haters.

Pros: Since the shortest system is the most efficient, getting rid of the ABS instead of pulling the fuse makes for a better braking experience. Better pedal feel, less chance for air to get trapped in the system, less fluid used. Weight reduction, about 30 lbs with the pump, old lines, wiring and harness. Some unspung weight savings by removing the ABS sensors.

Cons: You could kill your car or yourself if you aren't careful. Basically no going back once you start this mod.

THE TOOLS

10mm flare nut wrench

12mm socket/wrench

Metric allen wrench

Vise grips

10 gauge wire

Rubber hose for insulating the lines

Metal file

Small hacksaw (recommended)

Flexible, stainless steel lines, various lengths (way easier, for ballers) from Pegasus. Bling.

OR

Brake hardlines (harder to do, costs less). Ask to see the brake hardines at Kragen or Pep Boys, they keep them in the back, off the floor. Make sure you check the tag carefully, it must say Japanese, not British or American. The Brits use bubble flare instead of double flare, and the American fittings won't work with our parts. Get one really long piece, two or three medium ones and a four or five small ones (depending on your application). IMPORTANT: Be sure to get hardline that has fittings that thread all the way to the end, not the ones with a threadless end.

2 brass T fittings. They sell these at Kragen, too. Ask to see their brass fittings, they keep them under the parts counter desk. Root through it and find a couple of metric Ts that fit. Make sure it accepts double flares and isn't hollow or bubble flare. Maybe take a small piece of Japanese hardline and double check that it threads all the way on. Just pop the T out of the bag, no one ever buys this stuff anyway. You only need two but if there's an extra, it might be good to take it.

OR

You can order nicer, higher quality T fittings from Pegasus.

Double flare tool from Pep Boys (~$30)

Your proportioning valve or an optional 02+ WRX or Wilwood adjustable proportioning valve which makes the project much, much easier. Don't mix and match proportioning valves, though. If the prop valve was for a 4WDB car, don't use it if you have drums.



THE WAY

Remove the battery and pump the brakes a few time to get any current out.
Take out the intercooler, intake, strut tower braces, etc. that might get in the way. You need a lot of space in the bay for parts of this project.
Put the car on jacks and take the wheels off.
Drain the fluid out of your brake system.

Disconnect the wiring harness from the pump. Start attacking the hardlines coming out of the ABS pump, you won't need any of them so use the hacksaw if it makes things easier. Pop the nuts off with your flare wrench. It might take a lot of torque or they might be mashed up. Use PB liberally. Use vice grips if you have to. There should be two hardlines coming through the firewall that connect to the prop valve, don't cut these, but take out everything else. The pump is attached with 12mm bolts. Eventually you should be left with the MC, the two lines that go through the firewall, the prop valve and the brake lines that come off the calipers. Throw everything else away.
 

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Discussion Starter #2 (Edited)
OK, now your ready to make your lines, the hard part.

Take the master cylinder and bolt it on to the booster. Bolt the proportioning valve in place and connect the two hardlines from the firewall. Figure out a plan of attack for how your going to route your lines. You need to take the two lines out of the MC and connect them each to a T. Off of each T, a hardline goes to each front wheel well. Here's the tricky part, if one T sends one line to the right front, the other end end must connect with the left rear, and vice versa. You want the braking system to make a crossover or X configuration for safety, in case the other line fails. That way your brakes won't be both left or right wheels if something bad happens.

Pull out your seats, pull up your carpet and trace the two hardlines from the firewall. You might have to look around the rear axle with a flashlight to see which line goes to the left or right rear wheel.

Optional:

Pull the seats out and get rid of the ABS ECU. It's the large device that sits under the driver's side seat area with blue plugs with ABS printed on it. Trace the wires and clip them where they connect with the main harness. Be very careful when cutting wires. If you're not 100% sure it's the right wire from the ABS computer, don't cut it. The computer is surprisingly heavy.

Go back to the engine bay and study the proportioning valve. You figured out which of the two lines that go through the firewall goes to the right and left rear wheels. Follow that path on the prop valve to the other end, where it will accept the hardline coming from the T. The third end of the T will go to the opposite wheel (remember, right rear goes to left front and left rear goes to right front).

Take some 10 gauge wire and start mocking up the lines. Start from the MC and go to the two Ts. Then hold the T in the approximate location and take some more wire and mock up a route up to the prop valve. This is the hardest part without a WRX prop valve, because you'll have to be a bit creative with the route. Once you have your four routes, put them aside. Unbolt the prop valve and MC. Don't worry about mocking up the two other lines going to the front wheels, we'll do those later.

Go over to your bench and re-create the setup with the MC, PV and four routes. Stick the ends of the wires into their receptors on the MC and PV. Take four more pieces of wire and duplicate the routes. Once duplicated, straighten out the duplicates. This will give you the proper length for the new hardlines.

Using the cutting wheel in your double flare tool kit, cut off the hardline to the appropriate length. You can use vise grips on the end you're not using to make spinning the cutting wheel easier. You should now have four hardlines with one end cut off and eight fittings. Slip the fittings on the hardline back to back. Now you're ready to double flare the cut end. Follow the instructions on the back. It's pretty easy once you get the hang of it. File down the rough edge from where the clamp bit into the hardline. Important because you want the fitting to thread nicely. Make sure there is no grit or filings on the end of the hardline or in the MC/PV receptors.

I highly encourage you to practice flaring on scratch hardlines a few times until you can get nice, round, symetrical flares. Torque the flare tool down evenly and slowly. If you overtorque it, it wil make a too-big or lopsided flare. If they're lopsided, they won't fit right and your brake system WILL leak. Make sure the two pieces of the clamping tool are PERFECTLY flush with each other, otherwise you get lopsided flares. Go slowly and be patient.

Now bend the hardlines to shape and replace them one by one with the wire routes, finger tight at first. Does everything look right and fit snugly? If it looks good take it over to the bay and test fit it. Adjust/re-do lines as necessary. Once you're happy with it, take it back to the bench and torque down the fittings with your flare nut wrench, starting from the MC and working your way down. Make sure you get a very tight fit at each connection. To test the fitting, grab the hardline and each fitting and see if you can jiggle the line or hear any clicking. If there is any movement in the line within the fitting at all, do it again or else it will leak. They should be completely frozen in place.

It should look something like this:



Take the MC/PV back to the bay and bolt it in place and attach the two hardlines from the firewall to the PV. You should have two open ends on the Ts. Take some more wire and make a route to each wheel, mindful that you might have an intercooler or intake that has to go back. Cut and flare the lines, then fit them to the Ts. Hook up your flexible brake lines from the calipers to the hardlines. Fill the MC with DISTILLED water and check for leaks from your Ts and the MC/PV.

This is a picture of Brydon's BIG ASS TURBO...and his '02 WRX proportioning valve. Can you see how much easier it would be with this valve rather than mine? Spring for it if you can afford it.



Here is a picture of the final setup.



The hardline going to the passenger front (I'm RHD :D) is a little closer to the downpipe than I'd like but insulation using a split piece of rubber hose wrapped over the line like loom keeps it cool.



Since you've just deleted the ABS, you're probably pretty core. Might as well get rid of the last vestiges of the ABS system. Take off your front calipers, brake rotors and the dust shields (you might want to considering getting rid of these permanently, they retain heat on the rotor). You should see a notched silver colored ring around the axle and a dark magnetic sensor hanging off the hub that almost touches it. This is the ABS wheel lock sensor. Unbolt the magnetic sensor from the control arm. It will still be stuck on the bracket. A few good whacks right plumb on the sensor with a BFH should knock it through the bracket. Remove the sensor and the wiring to the wheel well. Undo the small bolts holding the silver ring in place with your metric allen wrech. Take your hacksaw and saw through the thinner section of the ring. Now grab a lever (like your file or a long socket wrench extension) and break the ring. It's weak metal, it should snap into halves.

Bleed the heck out of your brakes, double checking for leaks, put on your wheels and enjoy.

 

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1998 Forester on Orange 57F
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So the real question is do you like it?
 

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98rsti RallybluePearl
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great process always wanted to do this i do it the pussy pull the fuse way aha

How long does this usually take? maybe if you live close enough i could come have you do this for my car and give you a hand and some GREEN?
 

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2015 WRX STI WRB
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i wanna do this so bad but i had really bad luck changing out the stock brake lines. lol i hate that abs unit in the bay and it doesnt do anything.
 

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Discussion Starter #9
I just thought of another benefit of getting rid of the ABS: You'll be able to use higher-spec silicon DOT 5 brake fluid. ABS doesn't like silicon. You can bleed your brakes in no time, the system is so short. And the brake pedal really bites down without all of the superfluous stuff. Better brake feel.

It could take anywhere from half a day to a full weekend depending on how it goes with flaring the lines. If you can afford the flexible lines, get them. It will make it much easier. Maybe buy the double flare kit and a few small pieces of lines before hand and practice making flares, then do the delete. I'd do it for you but once was enough for me on this project. ;)

Pictures of the final setup, with the insulation on the lines:

 

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i did a little research on this a while back.

couldnt you just buy the prebent non-ABS brake lines from a early impreza L, use a AWDB prop valve from an 02 wrx, and call it a day?

it seems like it work work just like oem to me, but i didnt actually get around to deleting the ABS yet so i dont know.

just a thought.

nice diy

down with ABS!
 

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pre-bent L- lines are are $150 from subaru.

i would bend the lines myself too...its a good chance to re-route them and hide them...i have a bunch of line and flaring tools.

i just never got around to doing to conversion....maybe one weekend this summer ill get bored and make this my weekend project.
 

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1996 Impreza L/WRX swap
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i believe the abs light comes on the way we did it...not positive though.

we did this on the Project L...works great! might as well do the whole car and put in a hydro ebrake too. you can buy brakelines from checker/oreilly that can be bent by hand, no tools needed...i'd HIGHLY advise using these, makes life much easier.

make sure to practice double flaring before you begin this mod or else you are going to have leakage issues.

Justin
www.grimmspeed.com
 
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