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Ok, so do you plumb it it the front or rear circuit? as you know it only reduces pressure to that circuit, so do you plumb it in the rear and leave it fully open when you want rear brake or plumb it in the front to reduce the amount of front brake? plumbing in the front would be harder, but thats what ill do if necessary.

Stuart,,,Actually it not off topic mate,,,very on topic. The boys have a screw valve one thats will be tapped into the brake lines.

It's not always really necessary but a great advantage.

If you have changed to bigger calipers and discs then it becomes vital especially in bad weather where you might need more rear brakes.

Neil.

Ok, so do you plumb it it the front or rear circuit? as you know it only reduces pressure to that circuit, so do you plumb it in the rear and leave it fully open when you want rear brake or plumb it in the front to reduce the amount of front brake? plumbing in the front would be harder, but thats what ill do if necessary.

I plumbed mine up in the rear circuit so the fronts will get full flow, full pressure and i can reduce some of the flow/pressure in the rear system so i don't lock up the rears. Well that is the idea anyways i will let you know how it goes after Bathurst sprints. I got all my bits from Race Brakes Sydney, Matt is easy to deal with.

GL

Ive got some part numbers out of the rocket catalouge, what kind of money should you pay for a valve?

I plumbed mine up in the rear circuit so the fronts will get full flow, full pressure and i can reduce some of the flow/pressure in the rear system so i don't lock up the rears. Well that is the idea anyways i will let you know how it goes after Bathurst sprints. I got all my bits from Race Brakes Sydney, Matt is easy to deal with.

GL

Thanks for the info on the brake bias thing :D

i was going to go a pedal box with adjustable incabin setup, since i have f50's on the front and standard brakes on the rear.. one would say they are well out of balance at the moment.

My second Gtr gets delivered next week :) will be pinching some bits and selling off the rest to find the build :blink:

yeh, have seen that set-up, looking for a valve with a de-tent set up so you can count the turns of adjustment.

Thanks for the info on the brake bias thing :huh:

i was going to go a pedal box with adjustable incabin setup, since i have f50's on the front and standard brakes on the rear.. one would say they are well out of balance at the moment.

My second Gtr gets delivered next week :thumbsup: will be pinching some bits and selling off the rest to find the build :ph34r:

yeh, have seen that set-up, looking for a valve with a de-tent set up so you can count the turns of adjustment.

My friend has a willwood setup on his Sprinter. it has no markings on it but it clicks as he turns the knob and works quiet well.

*untill someone turns the knob when he isnt looking and spins out on the first corner.

is it the one with the blue knob? if so can it be used without the pedal box set-up as it says something about balance bars etc. i didnt understand.

My friend has a willwood setup on his Sprinter. it has no markings on it but it clicks as he turns the knob and works quiet well.

*untill someone turns the knob when he isnt looking and spins out on the first corner.

Please someone correct me if i'm wrong.

If you have bigger after-market front brakes and factory rears wouldn't you put the adjuster on the front. Putting the adjuster on the rears would do nothing to increase there efectiveness. Surely if you wanted more rear bias you would decrease the fronts.

Oh and another question,,,is there a factory regulator already in the system,,,most other cars have them.

Neil.

The other thing people dont understand is master cylinder sizing.

F50's you'll get away without bias controllers

As for fitting pedal boxes etc, unless you have an absolute need for it, a cage in the way of the booster or calipers that require larger than available masters then id advise you away from doing it.

Im all for pedal boxes when used in the right application but Seriously the expense of doing it properly can be much better spent on suspension parts or even better driver training which will ultimatly make you and the car quicker.

Neil your right but everyone does use them on the rear lines. It mearly restricts the applied pressure to the calipers making them lock latter. Problem is people dont match the master right and the pedal stroke to opperate the fronts becomes longer and thus causing the rears to lock at the same ammount of pedal stroke as they did with the OEM caliper. Restricting the front defeats the purpose of fitting them at all.

saying that Andrew I happen to have a bolt in Pedal box for a Nissan. No masters but its complete with balance bar etc.

Edited by Risking
Please someone correct me if i'm wrong.

If you have bigger after-market front brakes and factory rears wouldn't you put the adjuster on the front. Putting the adjuster on the rears would do nothing to increase there efectiveness. Surely if you wanted more rear bias you would decrease the fronts.

Oh and another question,,,is there a factory regulator already in the system,,,most other cars have them.

Neil.

I got a larger master cylinder to reduce the amount of pedal travel with the new brakes and it did not have a proportional valve, I just fitted the adjuster to be safe incase they started to lock up on me.

I will see how it goes.

Okay cool I understand whats being said. If you are not fixing the master/booster problem then the adjuster is just a band-aid fix and thats not what it's for.

Risking do you adjust yours for different tracks?.

I play a little in the Radical but almost always go back to where I had it in the 1st place.

What actually concerns me with having it on the rear is it will not increase rear bias.

So in the rain or with a full tank you are stuck with a crappy setup.

Neil.

If you have no prop valve in the master then a Bias trim is essential. We've tryed without and you'll lock rears all day long

Neil I have found with the Balance bar on tighter circuits the car is quicker with more front bias, probably due to the weight transfering to the front better and improving turn in. The flip flop at Oran park is a big one there. Flat out top of third, slight left foot brake just before the car changes direction and its happy. If I dont have enough front Bias the weight doesn't shift enough as its on the brake and the car tends to push to wide. It simply wont do that on any tire other than a good slick either.

However at the creek it doesnt really seem to make a big difference so like you I tend to go back to a "central point"

Ive found wet weather it needs loads more to the rear or else the fronts bite as it turns in.

so realistically for the amature doing track days, practice days and the ocassional sprint you can get away without it. and if you run it in the rear circuit it will aid in tighter circuits. if it rains you go home like the drag boys do lol. im still running the standard master with r33 booster and the G4s front & rear. I guess its a case of suck it & see. I read a story on the Stop Tech web site and it got pretty full on into where the pressure is actually applied relative to the pedal pressure and stroke. i had to have a few beers and read it again to understand that i didnt really understand and should just ask you guys. im not driving a super taxi and i guess most guys who do wouldnt understand either, they just have an engineer tell them turn brake bias two clicks clockwise. everything was so simple when you didnt have to worry about brakeing and turning.

If you have no prop valve in the master then a Bias trim is essential. We've tryed without and you'll lock rears all day long

Neil I have found with the Balance bar on tighter circuits the car is quicker with more front bias, probably due to the weight transfering to the front better and improving turn in. The flip flop at Oran park is a big one there. Flat out top of third, slight left foot brake just before the car changes direction and its happy. If I dont have enough front Bias the weight doesn't shift enough as its on the brake and the car tends to push to wide. It simply wont do that on any tire other than a good slick either.

However at the creek it doesnt really seem to make a big difference so like you I tend to go back to a "central point"

Ive found wet weather it needs loads more to the rear or else the fronts bite as it turns in.

Brake bias is largely subject to the drivers feel and there is no exact right answer. Some like a little lock up to let the rear end loose to encourage a bit of oversteer. In the wet, where your tyres can lock too easily and aquaplane, turn the rear down to make the car a little more controllable.

Many, many people change the front brakes, myself and Duncan included, without changing the rear and just leaving the factory proportioning valve in place. Done partly because we are cheap, but mostly because the rules don't mention a proportioning valve being allowed and it just doesn't seem to be necessary in most cases.

Of the hundreds of Targa cars and combined touring cars that I have seen with upgraded front brakes, I can only remember 2 that had adjustable proportioning valves, and one of the was an N13 GTiR which had to run standard 14" wheels and had a very unusual brake setup. That being said, my back end did come loose in the rain and sort of send me over a cliff, so maybe they should be in more cars!

One thing you do need to make sure to do if you do put one in is to remove the factory one. It's a little square box near the clutch slave cylinder. Lucky for us Nissan provides us with a little joining block on the driver side wheel arch in the engine bay that is generally removed when doing a custom brake setup with a proportioning valve and no ABS, so you can use it for just this problem!

is it the one with the blue knob? if so can it be used without the pedal box set-up as it says something about balance bars etc. i didnt understand.

Nope its a red knob, he has the whole wilwood pedal box setup for brake and clutch. with 3 remote canisters. i think its setup to a balance bar (if thats the thing i am thinking of) kinda moves a bar between the front and rear canisters.

The other thing people dont understand is master cylinder sizing.

F50's you'll get away without bias controllers

As for fitting pedal boxes etc, unless you have an absolute need for it, a cage in the way of the booster or calipers that require larger than available masters then id advise you away from doing it.

Im all for pedal boxes when used in the right application but Seriously the expense of doing it properly can be much better spent on suspension parts or even better driver training which will ultimatly make you and the car quicker.

Neil your right but everyone does use them on the rear lines. It mearly restricts the applied pressure to the calipers making them lock latter. Problem is people dont match the master right and the pedal stroke to opperate the fronts becomes longer and thus causing the rears to lock at the same ammount of pedal stroke as they did with the OEM caliper. Restricting the front defeats the purpose of fitting them at all.

saying that Andrew I happen to have a bolt in Pedal box for a Nissan. No masters but its complete with balance bar etc.

I think you are right would seem like a headache and an unnecessary item for me.. driver training is in need :) and a Motor!1$!@#%@!$^

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