Keith et al,
Many years ago Ken Davies and I were chatting to Derek Hurlock at Thames Ditton. At the time Ken was racing AE 108 very successfully and seeing off the Bristol and Ford engined cars. Our conversation turned to brakes and Derek remarked how much trouble they had taken, with Girling, to get the rear brakes to lock first. Ken and I were speechless as Derek went on to explain the philosophy: As the front wheels did the steering it was essential that they did not lock. Afterwards we both realised that many Aces and Acecas and Greyhounds we had driven had indeed suffered from this rear locking malady.
It was common practice, at the time, for Ace racers to fit smaller rear wheel cylinders to get a better front to rear balance. The usual fix being to go to a 7/8" cylinder instead of the 1". However Ken had also tried to improve his lap times by fitting disc front brakes to '108 and this necessitated a further reduction in rear brake effort by going down to 3/4" cylinders. When it transpired that the front drums had produced better lap times than the heavier discs he reverted to the Alfins, but retained the 3/4" rear cylinders. This combination turned out to be the best of all with a hard pedal and good front to rear balance.
I recollect that the smaller size Girling slave cylinders sometimes had three mounting studs instead of two, the extra stud was simply cut off as the remaining two fitted the rear mounting holes. By the bye, just a reminder, these studs fit in to slots which allow for the cylinder to shift. It is important not to do the nuts up tight. Originally there were spring washers under the nuts, but these are now most often missing. The wheel cylinder movement is essential to allow the linings to centre up in the drum.
So far as brake bleeding goes I gave up pumping brakes pedals and wasting pints of fluid trying to get the air bubbles out, years ago. I use a simple hand operated vacuum pump - there are several on the market, mine is a 'Mityvac' and it has worked fine for a long time. Just remember to put the bleed nipples in with PTFE tape around the threads so that air cannot be sucked in during bleeding operations with the nipple released.
James to fit replacement spring mounting bolts you will need to remove the diff from the rear spring tower. Fitting lowering blocks to the springs is not the way it was done in period and by reason of the Ace's unconventional suspension geometry might well be detrimental to cornering performance. The correct procedure was to re-temper the the springs to a lower arch and to shorten the main plate and the lap plate to retain the negative camber, or even increase it.
Barrie