I will try to get hold of a master cylinder from a 105 model (with standing pedals). I don't know how to fit it yet, but certainly that should work?
I can't guarantee that the clutch master cylinder from a 105 model (with standing pedals) will work in your 101. Two points:
- I have a clutch master cylinder from a 105 model (with standing pedals) in my '66 Sprint GT, combined with the type of slave cylinder pictured in post #5 and it works fine. So yes, that master-slave combination can work well.
- However, I don't know what distance the 101 pedal assembly moves your clutch master's input rod. The 105 pedal box was designed to actuate a hydraulic clutch master and may have a longer lever (than the 101 box) to give more travel.
There are a lot of considerations whenever you re-engineer something. For this problem, the product of the shaft movement and the master cylinder area must match what Alfa used on hydraulic clutch cars. If your 101 pedal assembly only pushes the rod for 3/4 the distance that the 105 pedal did, then you need a master with 1-1/3 the area to get the same fluid displacement.
Since you already have a bracket for a Girling clutch master welded into your car, if the Girling cylinder is too small, a simpler solution might just be to try finding a larger diameter Girling cylinder that will bolt into the same bracket.
Or, perhaps the Girling cylinder that you have is sized properly, but its seals have worn out.
Note that the master cylinder from a 105 model (with standing pedals) mounts very differently than the Girling cylinder that you pictured (see first photo below). If you decide to use an Alfa clutch master, one from a GTV-6 will be more similar (see second photo below).