R32, Abs, Rears Locking Up..

[luke20t]

hey all

i have a r32 gts4, recently did some brake upgrades which include:

RDA slotted / dimpled rotors all round, braided lines, cusco master cyl stopper, r32 gtr front calipers and ds2500 pads and new motul fluid.

the brakes seem to work quite well now, unless i hit the brakes quite hard and the rears lock up and the car has abs..

never needed to hit the brakes hard b4 the upgrade so dont know if the abs was working before.

the car has had a rb26 conversion, maybe thats got sumthin to do with it?

cheers

[BHDave]

Check the obvious stuff like speed sensor is still hooked up and the diff sensor is plugged in. If the wiring for the swap has been done properly it shouldn't contribute, but it's pretty common to have no speed sensor connected to the ecu after a swap.

[sav man]

how bad does it lock up? R32 ABS is very dosile, it takes a while (relitivly) to kick in.

[luke20t]

nar, the rears fully lock up.

where is the speed sensor located?

[dangerous_daveo]

Could it be the larger front brakes with the better quality pads causing the front to work more effecently than the rears and the system just overloading?

[luke20t]

the rears also have ds2500's

[djr81]

R32 GT-R's brakes are somewhat rear biased and usually lock the rears first. So what you are experiencing is nothing abnormal, unless ofcourse it is happening with very little retardation.

Some questions:

How firm is the pedal?

Does the ABS release the wheel, ie do you get the usual ABS feedback through the pedal, albeit at a slow rate because the system is pretty slow?

[luke20t]

the pedal is quite firm

i dont get any abs at all.

[luke20t]

oh and the abs warning light isnt on.