[stephen low]

The G Force was a derivative off the RMC's and if I recall rightly both kits originally specified Sigma Booster and XF master.

My partially built kit came with this gear so am less fanmiliar not having had to source it.

The only tweak I've yet to test out, though it has been made, was to swap crack valves in the booster. This arose as my engineer passed the braking test when it went through engineering but suggested the car could loose some pressure off the front brakes.

Doing this would allow added performance from the rear braking just prior to front lock up providing an overall improved braking performance.

Am yet to road test the modifications that were done. The only crack valve my brake specialist could suggest for my master was from a WP statemen I think. Typically a harder to get model but I percerviered on ebay and one came up.

Think I also recall the master being off a wagon and this issue may not be anywhere near as pointed if you use a ute based item. The allowance for weight would then be far more similar and the master would have been designed to suit this set up.

Good luck.