[400TT]

Sambo, I would expect these guys are changing front calipers to units with more suitable piston sizes to optimise the front and rear brake balance.

I know the skyline calipers have a lot smaller piston area than the 2-piston PBR units.

Same deal with Jag brakes, you want to fit a front caliper with smaller piston area to get more rear brake bias.

Even fitting a 2-piston PBR instead of Jag 4 piston improves the brake balance.

Sambo, what is your brake balance like?