Info - bore of standard brake master cylinder?

I’m trying to work out best sizes for master cylinders on a bias bar - ideally would like to know the standard master cylinder bore size (Mk1, standard car).


It’s 0.75"

I’m getting the bias bar built with .7" and .551" masters (to match 4-pot front and 2-pot rears on 295mm disks all round - static bias 53/47% (vs 73/27% standard). Should give identical pedal travel too.

May I ask which front caliper are you using?
Is it ok with static bias 53/47%?
I haven�t done the calculations (as I don�t know the front piston area you are using), but it sounds that the bias numbers might be wrong (as it applies almost equal force to the front and rear brakes). How did you derived that ratio?
Sorry for the questions, but I am in the �front calipers searching process�.

Front caliper 5040-10/11 (4 x 1.5")
Rear caliper HiSpec 2 x 1.625"

Static bias 53/47 should be OK - it’s about what an F1 car is - given the limited weight shift with stiff springs (very subjective assessment that). I’ve locked fronts in the dry, never locked the rears. The bias bar will give a range of bias from 75/25 (roughly standard road) to 35/65 (very rear biased!).

I found a ready to use spread sheet to calculate bias on