Hel me size brake M/C for dual setup

[mmasse]

Hi,

I would like to fabricate a dual m/c setup copying kyhunting design below.

I would need help in sizing the master cylinders for my brake calipers setup. I am running Brembo F40 calipers on the front (BIG!!) and 965 caliper on the rear. Currently I have a 23mm master cylinder but the feeling of the pedal is not right. There is too much pedal travel. I assume it is due to the very large front calipers. I also have a problem with the brake balance. Front weels lock too early. I have adjusted brake pads and addressed it a bit but still under hard braking front weels tend to lock too soon, so I think the dual setup with balance bar would allow me to setup it up for a more optimal brake balance.

Could anyone guide me on appropriate master cylinder size for front and rear?

Thanks

[Bill Verburg]

Originally Posted by mmasse

Hi,

I would like to fabricate a dual m/c setup copying kyhunting design below.

I would need help in sizing the master cylinders for my brake calipers setup. I am running Brembo F40 calipers on the front (BIG!!) and 965 caliper on the rear. Currently I have a 23mm master cylinder but the feeling of the pedal is not right. There is too much pedal travel. I assume it is due to the very large front calipers. I also have a problem with the brake balance. Front weels lock too early. I have adjusted brake pads and addressed it a bit but still under hard braking front weels tend to lock too soon, so I think the dual setup with balance bar would allow me to setup it up for a more optimal brake balance.

Could anyone guide me on appropriate master cylinder size for front and rear?

Thanks

I can run some #s for you but need to know the front pistons sizes, should be either 40/44 or 36/40, the 965 rears are 30/34. Also need to know the rotor sizes.

[mmasse]

Hi Bill
They are 38/44 mm

Thanks a lot!!

[Bill Verburg]

Originally Posted by mmasse

Hi Bill
They are 38/44 mm

Thanks a lot!!

rotor diameters?

[mmasse]

14inch

[Bill Verburg]

Originally Posted by mmasse

14inch

so 355.6mm just in front or all around? If not 335.6 in back what rotor are you using stock SC, 930, custom?

[mmasse]

Sorry Bill.

I have 14 inches rotors in the front and 930 rotors in the rear

[AVDCAV]

Call the guys at Engineered components " they are serious brake guys
As other posters have said, your missing a ton of information if you want this setup
Spot on .

[Bill Verburg]

Originally Posted by mmasse

Sorry Bill.

I have 14 inches rotors in the front and 930 rotors in the rear

Ok
3/4"(19.05mm( for the front and 5/8"(15.875mm) for the back gives you a brake torque bias of ~1.5 and a pedal ratio of ~33.7

for comparison my 993Cup clone has bias of 1.426 and a pedal ratio of 33.7

as long as you car is low stiff and has an effective lsd that is a great place to be

a stock 911 w/ A or S/M is 1.491 & 41.3, for performance use you want the lower pedal ratio

[mmasse]

Thanks a lot Bill...you are tha Man!!!!

[mmasse]

Look what I came across. Suddenly it seems that the project will be easier!!

Bill, I assume with the RSR pedal cluster is only a matter of fitting the right m/c and it would be a direct fit, right? or I am missing something?