[PeterAllen]

That’s not a bad idea 'sambo' and it might show if one port is pushing more fluid than another, or if there are pressure equalising bore holes, etc, but I would like a written or verbal explanation of the functionality of the m/c. I believe (but I’m not certain) that the proportioning on a Ute takes place at the rear where a sensor distributes the brake bias according to the load being carried. I’m hoping that means the m/c puts out equal pressure through both ports and the stand-alone proportioning valve (Wilwood) I’m fitting can be adjusted to the correct bias - via some trial and error.

Probably the only person who knows is a Holden engineer who worked on the design but who is now living off a redundancy package! Remember the good old days when a mechanic knew something about cars and did more than ‘remove and replace’.