clutch master cylinder sizes
Turbo Mini Forums

got a whole brake/clutch set up off a track car, and need a bit of an education on master cylinder sizes.



theyre both 7/8 bore



will these be any good?

Ive tried searching, but all i can find is questions about rear wheel cylinders with 4 pots...

anyone use this sort of set up?

cheers

Joe

Edited by joeybaby83 on 6th Sep, 2007.

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

i have a 3/4 for my clutch which seems to work well

I then put a 7/8's for my brakes, and i think it was a mistake. It wouldnt work well at all with the s set up, a very wooden feel that you couldnt get any confidence with

i then put on some alloy four pots and the feel is better, but not what i call ideal. Comically i did eject my mate out of the seat when i forgot to tell him i was testing them

i believe paul wigington uses a 7/8ths brake master cylinder, and calver says its what to use in the minispares articles

though looking on fastcarls twinengine jobbie and he uses a 3/4 brake master cylinder

cheers nic, granted i can see different sizes/combos causing different effects on the pad/disc pressure, which i dont really want to start on now as my heads still spinning from reading through past threads...but will touch on brakes later

as for the clutch though, where the slave travels over a set distance, wouldnt a larger bore m/c simply decrease the pedal travel and increase the effort slightly? ie do the same job differently?

or would i be risking over filling the slave and popping its piston out? and have to limit pedal travel?

whats the std clutch m/c bore?

joe

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Ive got 7/8 brake and 5/8 clutch, not that its much help joe as i havent even got the car running yet.

I have to be honest, this stuff confuses me the more i think about it

Small bore=higher pressure-less effort but more travel needed

Bigger bore = more fluid moved-more effort (harder pedal) less travel in pedal?

Try it, the clutch stop itself will stop the slave cylinder coming out too far


?!?!?!?!?!?! now my brain hurts

Where can you get the setups from like the one above?

Back once again like a renegade master

demon thieves and that sort of place

Joey-did that set up come off a mini or something else?

I had trouble getting enough travel on the pedals. In the end i had some custom clevis's made and then had to pop a 4mm spacer below the cylinders

Rally Design are your best bet for brake bits IMHO

http://www.rallydesign.co.uk/catalog/default.php

Every day is a school day ...........

How fast and how expensive ...... the same question...

Yeah, they are off a mini and came with a whole cars worth of braided hose and fittings (why I bought them tbh)

Im presuming a mig/7, but theres also a hydraulic handbrake, so possibly a rally car?

The rods/clevis's on these are past it anyway, LMA stock loads of bits to remedy this though, cheap too...

regarding letting the clutch stop nut limit the travel, on my old cooper I snapped the boss off the clutch arm when the std clutch flexy failed (turned into a one way valve), so not too keen on relying on that!

Joe

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Yikes!!!

Deffo try them. ITs the easiest bit to swap the master cylinders over, the pain in the ass is sorting out the fittings, which is a headache and expensive. A potential bargain

I imagine you will easily be able to sell 1 master cylinder if it turns out not to be right

just my luck, about to buy a couple of these:

http://www.apracing.com/car/cylinder/data.asp?code=CP6093

but none of the usual suspects have them in stock, can anyone get these local?

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

www.raceparts-direct.com

Got mine from there , had them in stock.

Rick

what size are you after?

I

3/4 or 19.1mm, with the 160mm 5/16 unf threaded rod, i think they are on that site though rick, illhave to dog out part numbers and check

cheers guys

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"