1 inch vr master cylinder to 5 ltr vr stato with ABS

[baza]

the stato has the standard 15 / 16 " m cylinder . i want to know if i can use a 1 inch master cylinder with the ABS if the extra front inlet port is blanked off [ on the 1 inch m- cylinder ]. note that the 1 inch m - cylinder will be a PBR unit as fitted to vr commodores . i really appreciate any advice if this can be done.....cheers .

 

[RX25SE]

Should be fine. You may notice the pedal a little firmer (harder to push).
I went fro 7/8" to 1" on my VS (before fitting VT calipers) and had quite a firm pedal but faster brake reaction.

As this is a brake modification, I recommend you confirm this with a brake specialist.

 

[baza]

Should be fine. You may notice the pedal a little firmer (harder to push).
I went fro 7/8" to 1" on my VS (before fitting VT calipers) and had quite a firm pedal but faster brake reaction.

As this is a brake modification, I recommend you confirm this with a brake specialist.

was your vs fitted with ABS brakes b4 you put on the 1" master ? you would have had to bend the brake pipes to connect to the master cylinder RX25SE .?

 

[Cheap6]

ABS and non-BS M/C are different, if that is part of the Q in the OP. The ABS M/C has an internal valve that allows fluid to be pumped back into the reservoir when fluid pressure is being dumped from a wheel cylinder. There will be no detectable difference in normal braking, only during an emergency stop in which the ABS is activated.

The M/C's can be ID'ed from the colour of the reservoirs.

 

[RX25SE]

was your vs fitted with ABS brakes b4 you put on the 1" master ? you would have had to bend the brake pipes to connect to the master cylinder RX25SE .?

Yes, fitted with factory ABS.
Replaced with a VT 1" master. No need to bend pipes but the VT master needs to be spaced away from the booster.

I thought all masters were the same. Well, there you go!

 

[baza]

Yes, fitted with factory ABS.
Replaced with a VT 1" master. No need to bend pipes but the VT master needs to be spaced away from the booster.

I thought all masters were the same. Well, there you go!

i think there has been a misunderstanding , i am refering to the 1 inch m-c fitted to vp series 2 and vr non ABS cars. the vt m-c is actually 1.25 inch. just want to know if i can use the non ABS vr 1 inch m-c on my vr 5 ltr stato ,but keep the ABS system. the 1 inch non ABS m-c just has an extra outlet on it . i want to know if the extra outlet can be blocked off and will the brakes be safe ?

 

[RX25SE]

i think there has been a misunderstanding , i am refering to the 1 inch m-c fitted to vp series 2 and vr non ABS cars. the vt m-c is actually 1.25 inch. just want to know if i can use the non ABS vr 1 inch m-c on my vr 5 ltr stato ,but keep the ABS system. the 1 inch non ABS m-c just has an extra outlet on it . i want to know if the extra outlet can be blocked off and will the brakes be safe ?

My apologies for the misunderstanding. I dont know if the 1" VP-R will suite your application.

FYI The VT m/cyl is actually a 1" bore but has a 1 1/8" fast fill chamber at the rear (the bit you can see). The VS is 7/8' bore with a 1 1/16 fast fill chamber.

 

[Cheap6]

i think there has been a misunderstanding , i am refering to the 1 inch m-c fitted to vp series 2 and vr non ABS cars. the vt m-c is actually 1.25 inch. just want to know if i can use the non ABS vr 1 inch m-c on my vr 5 ltr stato ,but keep the ABS system. the 1 inch non ABS m-c just has an extra outlet on it . i want to know if the extra outlet can be blocked off and will the brakes be safe ?

That's what I'm saying; the ABS won't work properly without the ABS M/C because the internals are different.

Under normal braking there won't be any difference.

When a wheel lock up is detected by the ABS computer, the first action is to block the wheel cylinder from the M/C and hold the wheel cylinder pressure, despite any increase of that in the M/C. This part will still work in the same way.

If the wheel doesn't start to turn again with that action the fluid in the wheel cylinder is opened to the inlet of the pump in the ABS module (under the bonnet). This is to reduce the fluid pressure at the wheel cylinder. The fluid is pumped against the pressure in the M/C back to the reservoir through a check valve - there isn't a flow of fluid, just an offset of pressure. The check valve is absent on non-ABS M/C's, so the dumping action won't happen.

 

[baza]

thanks RX25SE and CHEAPSIX , i wont do the 1 inch m - c seems to be the wrong move. today i bought a set of QFM pads for the front they might help brake performance.