Quote:
Originally Posted by CJMRSR
Thanks Bill. That is really helpful. I have nailed down my suspension spec.
I am just finalising my brakes setup. I have 930 brake callipers all round and a 930 brake master cylinder. I am tempted to do twin master cylinder pedal box. Do you think its worth it for a fast going road car that might get the odd track day? I take it I cannot use the 930 brake master cylinder with a twin master cylinder pedal box..? Ive read that the pedal spacing can be made less offset with the twin master cylinder pedal box..
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w/ 930 brakes a twin master isn't necessary but it would be icing on the cake so to speak.
930s give a brake torque bias of 1.579 and w/ a 23.8mm mc a pedal ratio of 33.105
both are good places to be
stock 72-'83 911 is 1.491 and 41.311 w/o vac. boost or 35.328 w/
I like that bias better but not the pedal ratios
w/ a low stiff car and effective lsd I have 1.426 on both of mine
using a twin master is a juggling context
for 930s w/ 5/8 & 5/8 the bias is the same but pedal goes to 37.18, this ok but a step in the wrong direction, depending on the exact design the bar can change bias from ~2 to ~1.28
using 7/10 and 5/8 bias goes to 1.444 w/ a pedal of 33.66 all good w/ a range of ~1.9 to ~1.1, you'll never likely want anything below 1.45
there
The issue is the lack of fine gradations in available m/c and the interaction w/ pedal ratio.
these are the commonly available m/c
in mm
5/8 15.88
7/10 17.78
3/4 19.05
13/16 20.64
7/8 22.23
15/16 23.81
1 25.40
1 1/8 28.58
Your car will be a hoot, I get such a big grin every time I get mine out