master cylinder sizing and type?

[rickjohnson356]

Ok, ball joints are fixed, so next up are the master cylinders....

Since the calipers and rotors are the same front/rear, and I will be installing a cockpit balance adjuster, what size brake mc should I be using for FST? my first guess would be 5/8" (.625 inch bore) for both front and rear. But 3/4 (.750) and .70 are also available.

[My FC used different sizes, but it had LD19 on one end and LD20 on the other.]

Any preference for a single remote resovoir (clear plastic with dual feeds) or use the mc with the resovoir built in (standard used on most FF/FC etc). I have only used the built in type before, but am considering the remote type for ease of checking the fluid level without having to remove the mc cap. One concern would be if the filler tubes from the remote resovoir leak or become disconnected easily/accidentally.

I might wind up using the ones without a built in resovoir anyway because of mounting issues under the front beam. ( I haven't measured yet to verify.)

While we are at it, what size should the clutch mc be? It would be nice to have all three the same, so that I only have to carry one spare and/or rebuild kit. I will be using the standard clutch slave cylinder sold by SR.

Thanks again folks!

[sracing]

Rick,

We can set you up most anyway you want. You are correct, I would use the .625 on the brakes and .70 or .75 on the clutch. (You can probably get by with the .625 on the clutch also, but clutch adjustment might be a little more critical.)

If you are concerned about spares, just carry a .625 spare. If you had a master cylinder problem on the clutch you could always use the .625 in a pinch. (and the clutch pedal is easier to push <g>)

We have integral and non-integral resevoir brakes. We also have a simple dual resevoir if you go with the non-intergral. http://sracing.com/Store/FV_Stuff/resevoir.jpg

Feel free to call.

Jim
SR 859-252-2496

[kea]

If your brake caliper pistons are the same size, front and rear, use different master bore sizes. That is the standard method, 5/8" front being popular. I like the integral masters from Girling, for quality and cost. If you require more volume, than use the Girling extensions on them.

[sracing]

If your brake caliper pistons are the same size, front and rear, use different master bore sizes.

He could do that also, but we have found with the FST, matching masters with a bias bar adjustment provides more than enough bias.

[kea]

I know it's been done that way, but the majority of vehicles have some type of mechanical bias, either calipers pistons/bore sizes or master cylinder bore, by design. So I would assume there is a performance reason for it.