boosterless brake plumbing

[artoo93]

Question for all the gurus out there. Searched and couldn't find the right answer. Maybe my search skills are failing me right now. I am going with a boosterless setup using the Garagastic pedal mount with Wilwood masters on Southwest Speed pedals. I also deleted the ABS from the car as well. I am trying to run the lines for the front brakes but I'm not sure the correct way to connect the two together. Can I just put a T block in or do I need to run some kind of proportioning valve? I still have the one that was under the master in the original setup but it has 2 inlets and 2 outlets. Can I just plug one inlet or is this valve 2 separate chambers? Or do I need something else altogether? Maybe someone can save my fried grey matter!!!!

[1991 e30 bmw 318is]

if you need a tee i got one at dealer for the rear brake lines for an e30 located at rear end.. but when i went hook mine up my mc had an extra port so i never used it.

[CLM21]

Well, theres an abs delete kit here that just connects one MC outlet straight to the rear line, and then tees the other MC outlet which goes to each front brake. Not sure if its technically the right way to do it, as im sure the flow isn't directly proportional doing it that way. But im no guru, and theres a decent amount of people who have done it that way and it seems to have worked fine thus far.

I'm actually in the process of doing this to my brake lines right now, and Lee from Massive (who knows a thing or two about brakes and MCs..) told me to do it that way. So Im sure its fine.

This is the "kit" Im talking about:

http://www.r3vlimited.com/board/showthread.php?t=275819

[e30_302]

Single master cylinder? Tee the fronts, run the rear through a prop valve into the line heading back.

[artoo93]

Running dual masters, one for each front and rear. I'll look into Lee's idea as well.

[e30_302]

Oh then that's easy, just tee it.

[artoo93]

^^^That's what I figured but figured I'd get some opinions of how others were doing theirs. Thanks!!

[M3 euro ltw]

This

Single master cylinder? Tee the fronts, run the rear through a prop valve into the line heading back.

What ever you do, if you've deleted the ABS, you must have a bias valve put in for the rear circuit.

Adjustable would be the way to go.

That having been said, the E36 ABS system is quite simple, and easily plumbed in given that there are 3 circuit versions.

Why not?

[CLM21]

Why do you need a bias valve when you delete abs? I was told to remove the pressure regulator on the rear channel when I went boosterless.... so is it just non-abs that needs the valve, and abs cars can delete the valve? So the rears lockup well before the fronts when you delete abs?

[artoo93]

I have a bias valve on the pedals so I will set everything with that. I kept the rear brake factory lines. I already removed all the wiring along with all the under hood parts of the abs. I've grown up driving vehicles that power steering and abs/boostered brakes were never even dreamt of. I'll get everything put together and see how it goes.

[M3 euro ltw]

Very, very late to the thread

You may have a bias BAR on the pedals, and yes, that can adjust static bias between front and rear circuit nicely.

A bias valve is a different beast, and it's purpose is to progressively emphasize, shift bias if you will, to the front as you brake harder.

The Modern ABS pumps/ABS computers do this FOR you. Brake Force Distribution or whatever term you like.... but its built into modern abs units, so you don't use a bias valve anymore. Take away the ABS on a car that was designed for it, and you've got a potentially dangerous situation, one where the back will lock up too quickly and spin you around fast.

This situation only gets worse the more modern the car is, because now, with so many active driving aids, the "natural" mechanical bias is shifting away from the old school mid 60% to 50% to allow better rear wheel braking for traction, stability control etc when needed...so without the ABS brake distribution "on" the cars are unstable almost when it fails.

MZ3 famous for misbehaving if you lose ABS..

The modern E46 M3 system is phenomenally quick at adjust bias on the fly to maximize braking. Hence its adoption by so many porsche cars.

came across this way after my initial post.

[Jean]

M3 euro ltw - just the guy I wanted to ask (I'll just use this thread as my situation is somewhat similar).

I have an 84 chassis, so no ABS from factory. The stock brake master cylinder has 3 hard lines, two for the front left/front right calipers and one line goes towards the back of the car.

Easy right?

Now, with the booster less setup, we get the wildwood pedal setup with 2 individual cylinders so we get 2 output lines for the 3 hardware lines in the engine bay .

How do I add a Bias valve when I have 2 lines coming out of the wildwood setup, and 3 lines in the engine bay for the FL, FR, and rear brakes?

Adjusting the bias bar that comes with the pedal box is going to be a HUGE pain in the butt, so I would like to set it and forget it,..,.but really need to be able to adjust the bias Front to Rear to dial it in correctly for autocross.

What's your recommendation ?

Is there a BIAS valve that would take 2 input lines and let me Bias front/rear ? I could add a T for the front left/front right...and end up with 2 lines under the hood (one for the front calipers and one for the rear)... I just don't know exactly how you are supposed to add a BIAS valve when you have TWO lines coming out of the pedal box.


Thanks much!

[M3 euro ltw]

Quick answer, long and extended PM sent to Jean.

You would put the bias valve on the single output of the rear master cylinder's output. It could be placed under the hood, for set and forget. This essentially duplicates what an E30M3 does for a bias valve to the rear of the car, but I'd agree, adjustable is better.

The other master cylinder's single output needs to be "T"ed to manage L&R front brakes, much like the single line going to the rear is "T"ed, but somewhere in the back, near the gas tank I'm guessing.

If you do not use a balance bar, it is NOT the end of the world, but, I would strongly suggest you let me have your mechanical data to help you select the proper pair of masters to get the brake bias where it should be.

To be honest, and you may not like to hear this, I would VERY strongly suggest you add ABS to your car. Specifically, the easiest and cheapest would be to get the E36 M3 OBD-1 system, ie the 3 channel ABS from say a 95 M3. These parts are cheap, plentiful, and easy to find, as well as, the harness for the ABS could be easily salvaged from any 3 channel ABS E36. I don't know the details of an 84, but if you're lucky, adding in ABS wheel speed sensors is easy.

The addition of ABS allows the ABS pump and DME to very, very quickly and perfectly adjust the front to rear bias for you, and then you don't want or need the adjustable bias valve. It will still make sense to properly size your pair of masters to match the hardware on your car. IE, I need brake rotor diameter, pad width measured radially, piston diameter and count on the calipers. Then remember to use same compound front and rear pads to negate differe Cf between them that would upset the bias.

Alex. (TMI?)

[Jean]

Alex, responded in PM . Thank you buddy!

re: wildwood 260-11179 appears to have 2 inlets and 3 outlets...if it will let me run the lines coming out of the wildwood pedal box with 2 masters to the 2 inlets of the valve and then 3 lines would be for the FR, FR and the 3rd for the rear line that would take care of this ?

Called Wildwood and they recommended adding this to the pedal box http://www.wilwood.com/Pedals/PedalP...temno=340-4990
The 260-11179 (http://www.wilwood.com/MasterCylinde...emno=260-11179) can take care of the "T" and let you "trim" the rear brake pressure, but doesn't do anything for the front/rear BIAS like the balance bar on the pedal box does.

[jpod999]

That 260-11179 prop valve is pretty cool, I may have run that had I known about it before I plumbed my system up. I went with an adjustable prop valve plumbed into the rear line, and a Tee for the fronts...wasn't too tough.