Outer Limits 4x4 Board

just wonderin if anybody knows the bore sizes of the zook brake master cylinders ???

and does anybody know if there is an upgrade or even another master that will bolt on with a larger bore size ???

im going 2 run 80 series diffs F&R under a zook and am just wonderin wot my options r or do i just get another booster and master form something else and make it fit ???

Yep, use a master cylinder from a Subaru Forester. These have a 1-1/16" bore and bolt straight to the Sierra booster.
This is 1/4" bigger than the stock bore.

Bazooka wrote:Yep, use a master cylinder from a Subaru Forester. These have a 1-1/16" bore and bolt straight to the Sierra booster.
This is 1/4" bigger than the stock bore.

r ok, thanx 4 that will look into it some more

what are the outlets like? are they the same thread? are these set up for rear disc with a properly set bias for the rear brakes?

The subaru outlets are in different locations but with some creative bending the lines will fit. They are the same thread.

Im no brake expert so I dont see how the master cylinder affects bias? Isnt it the same size piston running through the same size bore pushing the same amount of fluid, giving the same amount of pressure to both front and rear brakes? I thought to get bias at the master cylinder end you would need to run two cylinders and a balance bar for adjustment. Now I am curious to find out more about this.
Even though I am sure the subaru cylinder would be set up for the subaru system, putting it on a sierra, biased or not it may be useless.

Before I pulled my Sierra down to build it up from scratch I was planning on using the Subaru cylinder, rear Sierra discs and front Vitara discs. This way it should still be front biased. Its never going to be any flat track racer so getting the bias exactly right doesnt matter much.