Spoke to local brake shop and they have recomended fitment of new porportioning valve to suit disc's all round. It is not cheap and quite alot larger than 180b unit

They also sudjested hunting around the wreckers for another valve from a vehicle with disc brakes all round that uses this type of setup.

Spoke to Scott at Maddat and he is running straight from the master cylinder without a porportioning valve?

What should I do?

This setup is for Hilux 4 pot fronts and R31 rear and the 180B master and booster is already fitted to the car from the previous setup