rear brakes locking

[callum]

ive just put the front disks from an fxgt in my ae92 wagon and now when i hit the brakes hard the rears lock up before the fronts. what it this likely to be caused by and how can i fix it? also my car has D2 adjustables could this be affecting it?

[jakesae101]

bis valve needed possibly ?

[callum]

yeah i never changed it, however i dont really think it should be the problem since i have put bigger brakes on the front and left the rear drums standard

[Adoom]

I also think Bias valve. Get a Willwood adjustable one and replace the std valve with it. Thats what I did with my brake conversion.
Or you could fnck around with a bunch of non adjustable bias valves until you find one thats 'just right'.

What it(the adjustable one) does is reduce the pressure in the line you put it in. So you put it in the line to the rear and adjust it until the fronts lock up 'just' before the rears.
I would advise doing this on a nice straight road with $&#$% all or no traffic. No need to go real fast or anything, 50kph will the fine.

[callum]

sounds promising. where do you get them from and how much are they?

[KinLoud]

Hi,
exactly what have you done?
Have you put disks and calipers from fxgt onto your wagon? Or just disks?
Are the front brakes working at all?
What sort of fxgt? Was it superstrut? Calipers single pot or twin pot?
Did you have to change the hoses?
Did you do anything else to the braking system? Change pads, fluid, bleed brakes? etc?
Are the disks bigger diameter than before? or just thicker?

Ken
Auck
021 408 863

[Adoom]

sounds promising. where do you get them from and how much are they?

Road & Track in Lower Hutt sell them and Cardwells Racing somewhere in Auckland.
It depends where you live........ I think they are like $90 or $100 or something. I bought mine years ago so I dunno how much they are now.

[Bling]

How hard is hard? If you brake normally does it work work fine?

[random theory]
Maybe weight shifting to the front when you brake now due to more braking.
Which in turn takes weight off the rear and makes it easy for the rear to lock up.
[/random theory]

Would depend on how hard you have to brake to lock them though. But the above theory is just a theory

[jakesae101]

would think that bigger brakes at the front means its easyer for pressure to build at the rear

[callum]

ive put on the disks and calipers from an fxgt. the disks are the same dia but thicker (vented rather than the old solid ones i had on). the brakes are single pot.
the fronts are working but the rears lock up a fair bit before the fronts.
i dont think it was superstrut.
i didnt have to change any hoes i just bolted the old ones up to them.
other than that all i did was bled the brakes.

[FLAWLES]

brake baise valve is pretty extream, be a muck around to get wofs etc if its a streat car i would imagine

do those run a brake purportion valve?, if so make sure that is correct maybe the incoorect size for the upgrade you have done

most cars when the pedal is applyed the rear brakes get applied first then the front

if you have put bigger brakes on the back, you will have to do the same on the front to balance it all out

theres like a mathmatical equation behind it, blah blah piston sizes etc
i cant remember it