The brakes on the Urraco are reasonably advanced for the period. However they are not servo assisted. However with four pot callipers and ventilated discs all round they are powerful enough to cope with the Urraco which isnt hugely heavy. The front callipers which are in the pictures are actually from the 1972 BMW 5 series or the 2002 Ti However their is a spacer between the two halves of the calliper which allows for the wider disc used by Lamborghini. The rear callipers are from the standard 2002 although I havent changed these. I purchased a pair of front callipers which cost £110. I have the details if any one is interested. One thing to remember is not to lose the pins that hold the pads in place. The ones that come with the callipers are not long enough as they are for the thinner BMW discs.
On my car the master cylinder failed probably from being left without any fluid in it. The master cylinders are no longer available so I had the original one rebored which cost just over £100.