Do you think im using too much length of brake line by going from the handbrake, up into the firewall, then back down to the rear? Or perhaps the stock rear brake line is too small a diameter? In either case, this shouldnt make much difference to the workings? After all, pressure is pressure, whether it is in a small pipe or a large pipe. Tge pipes dont have to flow any great deal of volume. (just enough to expand the pistons in the calipers) so aslong as the pressure doesnt drop off, then it shouldnt matter how small of long the pipe is.

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Doing it for all the wagons out there

Honestly mate I'm unsure as from what I've seen you do in theory should work. The rear calipers have no trouble locking the rear brakes when I've done it before . I had the adjustable bias valve before the handbrake and didn't use the factory bias valve at all that's the only thing I can see different . Using the manual valve to adjust brake bias isn't an issue on rally or track cars as the car is stiffer and your not carrying loads or passengers which a factory valve will compensate for


Sent from under my Dok Dok

do ypu think there might be some other restrictor in the circuit? At the rear of the car under neath near where the diff oitrigger frame is, there is a brake line union on each side for the rear brakes. Do you think these may be sone type of restrictor?

If youve done it by totoally running new lines to rear, then it would bypas them. (if they are infact a restriction and not just a union.)

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Doing it for all the wagons out there

Possibly I've honestly. Never had the amount of trouble that you have encountered,but again haven't done it with abs . But can tell you for sure that the rear brakes lock on Tarmac and wont just slow the car down I wonder if through the abs the fluid is able to move to the front circuit as well when you pull the hand brake and it spreads the effort.


Sent from under my Dok Dok

I was at mms last week a few of there cars run that sti set uo might be worth a call or visit and asking

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Where have you connected the "outputs" from the handbrake cylinder to the rear brake lines?

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[SIGPIC][/SIGPIC]

All hydraluic connections are made at the valve block (rear proportioning valve) at the drivers strut tower. I ran 4 hardlines from there across to the passenger firewall. From there it goes through the firewall just below the main ECU loom pass through. From there it goes flexible hose direct to the handbrake cylinder. I used the 'output' of the rear bias valve as the junction point for everything. So the handbrake cylinder tee's in after the rear proportioning valve. If you look at the photo below, you can see the way the hardlines are routed in relation to the valve. I used that location as i *thought* it would be a good place to join in with the minimum of cutting into stock lines. I figured it had to be after the proportioning valve, otherwise that would limit the handbrake cylinder pressure to the rear calipers. I simply un-did the output fiittings of the bias valve. And screwed in my 4 hardlines in-between.

Basically the hydraulic circuit goes as follows.

Main tanden master cylinder > ABS valve block > rear proportioning valve > handbrake master cylinder > rear caliprs.

The main master cylinder is a GDB STi item. (Larger bore than SG Forester)

I have totoally removed and bypassed the hill holder, which used to be inbetween the main master and the ABS. In its place is a hardline i bent up to totoally remove it from the system.

The proportioning valve is also a GDB item. (Unsure if different to SG Forester, but suspect it is due to different brakes on both vehicles.)

Front brakes are Wilwood FNSL6R calipers.

Rear brakes are GDB STi Brembos. (Overhauled and painted before fitting)

Handbrake master cylinder is a Group N STi / AP Racing inline tandem with 7/10 inch bore. (Freshly overhauled before fitting.)





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Doing it for all the wagons out there

My current suspicion is perhaps the brembos just dont have enough piston volume? Maybe i need some AP 4 pot rears to really lock it on hard?

I reckon i could make the car skid if i yanked it while turning. But it will not lock up in a straight line. Maybe im expecting too much from it?

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Doing it for all the wagons out there

Only one way to find out...

What size / compound tyres you running because I imagine a 235 or 245 semi-slick would possibly outgrip the clamping pressure of your rear Brembos in a straight line situation. A simple (not cheap) solution is to, as you suggested, go to a larger rear brake set-up.

Once you have the car turning in then you can use the handbrake and vehicle inertia to overwhelm the tyres a lot easier.

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MY01 JDM EVO VII - 230KW / 430NM @ 1.6BAR

If u wanna do some testing i have heaps of paddock we can tare up ...my lancer was great fun handbrake drifting around haha

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