Bias valve or not?

[dr_jekyll]

Right looking into removing the abs.
If I run the 23mm gti-6 master cylinder (2 ports with splits in line) do I require a bias valve in line to distribute the brakes correctly? Or is this automaticaly done by the master cylinder?
[attachment=20186]

[Mattcheese31]

No, use the bias valve mate

[dr_jekyll]

Is there a standard bias valve for 306's? Seen the 4 port master cylinders and assumed it was controlled by the master cylinder

[bashbarnard]

Its called rear compensator. Its on the axle

[dr_jekyll]

If your on about the load compensator I deleted it with parts from my other 306.

[bashbarnard]

Then you really need a bias valve. I'm running no compensator ATM. Need to buy one for mine

[dr_jekyll]

Ok fella, cheers for that.
I pressume you only run a bias to the rear lines to turn it down and tame them?

[jamiek_uk2000]

The phase 1 GTi6 had the rear compensator, the phase 2/3 didn't have it as it was done by the ABS unit.

If you are taking the pipes straight to the rear (which it does sound like if you are taking the lines straight from the master cylinder) then you will have to have a bias valve somewhere. In the car allows for on the fly if your on a track and the weather get's wet. Can be under the bonnet as a fit and forget.

If you don't then you'll have 50/50 braking which will mean the back will lock up all the time

[swampy]

Yes you run it in the rear line.

Where you fit it is up to you, some people fit them under the bonnet others inside the car by the handbrake

I can supply willwood knob adjust ones for a good price

[dr_jekyll]

Thats the exact info I wanted will be under bonnet job as its a road car

[fatlapit]

u dont need alot to the rear
id go to a quiet open road and play with it

[dr_jekyll]

Will prob stick it on a brake tester and have a play

[Moonpie]

Fit one. 50/50 braking can be scary. ( tho can be fun lol)

[fatlapit]

i run 10% to the rear on mine. sometimes 20

[Stef205]

i dont run a bias valve at all in my 205, never had a issue. Just try it with out before jumping the gun.

[bashbarnard]

Right so today I looked round lus new car. Phase one kingfisher green that's rust free . But has a dead axle. What I did notice is that it has no abs and no load compensator. I have full history with the car. And I mean full even headlamp bulb receipts. No rear beam change therefore its original. I thought they all had a form of compensation on them

[Toms306]

Don't need a compensator with drums as far I as know. They're not efficient enough to need the brakeforce reducing lol.

[bashbarnard]

You sure all of mine had compenators with drums.

[Toms306]

Did they have ABS though?

I'm pretty sure non-ABS drum 306s don't have them but I'm sure someone will be along to correct me lol.

[bashbarnard]

Some did some didn't. All had compensators. Hope someone sheds some light on this.

[dr_jekyll]

Intresting. So could mean i havnt got to fit a bias maybe? Ngl havnt looked into it anymore as got overwealmed with sorting other niggles

[da_no1]

I have a standard Dturbo with rear drums from 1995 and it doesn't have ABS or rear compensator.

[welshpug]

they have inbuilt pressure limiters in the wheel cylinders, Drum ABS models have load compensators, late phase3 have EBD


drums really are as strong as a rear disc, hence the pressure limiters.

[bashbarnard]

Fair enough. That's new info for me. Least I know.

[Mattcheese31]

I think it depends which rear drums you have, they fitted girling and bendix iirc, small and big, the big ones have a load compensator I believe

[dr_jekyll]

Had a brake pipe fail the other day so gotta re-do it. Gonna do the abs delete without the bias to see if it works or not. Need to bleed the whole system again no matter what as also fitting braideds

[aggyj17]

If you run the brake pipes without a bias valve I would put a joiner near to where you would put the bias valve because if you need to run one it will be easier to fit it and wouldn't need to mess about as much