Is there an alternative master cylinder that gives better brake feel / action instead of the standard Sierra one?
I'm thinking that the Sierra master cylinder is designed for a (much) heavier car with servo assistance.
Requirements are:-
Must fit through existing hole in bulkhead.
Must be dual circuit.
Must use the same pipe fittings.
Ideally with an integral reservoir.
Oh and cheap!
Cheers
Mike
Theres some on the Rally Design website but not cheap!
That's exactly what Dave K and Peter said about my car when they drove it at the trackday.
I'm thinking the best option is to remove the sierra m/c, open up the bulkhead where the m/c fits and bolt in a thick ali plate with twin
cylinders so they can be adjusted via a balance bar.
I'm also going to mount a couple of remote reservoirs because the sierra unit is a right PITA top check fluid/top up. Obviously this will be a
post SVA mod as I won;t be fitting a fluid level sensor 
As already the subject of many threads what is needed is a smaller bore mastercylinder from a non-servo equiped car.
As cars without servos but with tandem dual circuit cylinders are rare the choices of donors are limmited.
(1) MK 1 Fiesta --- without srvo (most Mk1 Fiestas had servos.
(2) Mk 3 Cortina 1300 without srvo (most M3 Cortinas had servos)
(3) Early VW Pollo or Golf 1100 without servo
(4) Triumph Spitfire 1500 duak circuit.
(5) Some FX4 Taxi models.
The bolt pattern for these cylinders is different ie the standard no servo pattern.
As BT said and helped me out. I have the Fiesta Mk.1 but you do need a bit of modifying. I'm not sure you'd get away with replacing without some kind of faffing.
Thanks BT!
I have just checked the Brakes International site. Replacement tandem master cylinder for a Mk1 Fiasco is about £50.
Only trouble is, I'm not sure if that comes with the reservoir. If it doesn't it's a POA part!
The tina items are £150 plus, as are the FX4 items.
Thanks!
Mike
It doesn't come with reservoir if I remember. I went in and asked them. I think they wanted somewhere in the region of £70-£80 all in.
There's a fella on Ebay sells them for £50. I got mine from him and someone else on here got one too. Old stock but if it doesn't work
he'll take it back.
Edited to add I've just had a quick look and couldn't find any by him.
Something to be aware of with this MC apart from the bolt pattern is the 50/50 split. I had to put a bias valve in the rear line to keep things
balanced. I also had to cut the pushrod down to its very limit and it only just fits because of the angle of my pedal. On the flip side there's
loads of pedal travel now, almost too much but it passed SVA last week so it's fine by me.
[Edited on 26/4/09 by mistergrumpy]
[Edited on 26/4/09 by mistergrumpy]
i,m looking to do a similar upgrade,look at the fiat uno ones,£19 ish and 19mm dia.
my current master is a mondingo one,25.4mm,is this a jump too far?
Golf/Polo (non servo 1100 models) pattern 17.46mm dia master cylinders are available cheaply from Euro Car Parts and various other suppliers although stock levels are running out BUT you have to find a resevoir from the scrappies.
quote:
Originally posted by theconrodkid
i,m looking to do a similar upgrade,look at the fiat uno ones,£19 ish and 19mm dia.
my current master is a mondingo one,25.4mm,is this a jump too far?
looks like brakes international will be getting a call...cheers BT
i'm using one from caterham (westfield sell the same one) I went for the ap racing aluminium one £180 delivered.
I made an ali wedge-shaped spacer to fit between the sierra M/C and the bulkhead. This enables you to move the clevis further down the pedal, thus
increasing the pedal ratio. It also makes sure the sierra reservoir is level again. IIRC the angle on the spacer was 12 degrees.
The final overall ratio works out at something roughly similar to a fiesta M/C in the original mounting position.
Cost me nowt, though!
Well, the cars is back on the road and the brakes have improved vastly by fitting the spacer that increases the pedal ratio. Well worth the effort IMHO, cheaper then a new M/C and the reservoir top is now also level.
Hi Sebastian
Any chance you could post a couple of photos of the wedge??
Also did you make it yourself or get a machine shop to make it? I'd have to get a machine shop to make one for me, which would mean giving them
a drawing / set of dimensions.
Cheers
Mike
quote:
Originally posted by sebastiaan
I made an ali wedge-shaped spacer to fit between the sierra M/C and the bulkhead. This enables you to move the clevis further down the pedal, thus increasing the pedal ratio.
Yes, it went from 3 to 4,5. I'll see if I can get some pics this weekend.
The spacer is just a piece of ali cut at a 12 degree angle with a suitable hole in the middle for the M/C to pass through.
The spacer was cut on the bandsaw at work at a 12 degree angle from a piece of large diameter bar. Then a suitable hole was machined to fit the M/C
through (same diameter as the hole in the bulkhead, don't know the exact measurement. The spacer was then fitted between bulkhead and M/C with
some longer bolts. It could be trimmed down further but I did not bother with that since I wanted to see if it worked first. I was lucky enough that I
had enough spare length in my brake lines to not have to replace them.
Some pics...
brake spacer
brake spacer 2
brake spacer 3
brake spacer 4
brake spacer 5
quote:
Originally posted by sebastiaan
I made an ali wedge-shaped spacer to fit between the sierra M/C and the bulkhead. This enables you to move the clevis further down the pedal, thus increasing the pedal ratio. It also makes sure the sierra reservoir is level again. IIRC the angle on the spacer was 12 degrees.
The final overall ratio works out at something roughly similar to a fiesta M/C in the original mounting position.
Cost me nowt, though!
Problem: pedal ratio too low.
Solution: move clevis further down.
Execution: tilit M/C.
Simple, really ;-) but thanks for the compliment. 
quote:
Originally posted by britishtrident
As already the subject of many threads what is needed is a smaller bore mastercylinder from a non-servo equiped car.
As cars without servos but with tandem dual circuit cylinders are rare the choices of donors are limmited.
(1) MK 1 Fiesta --- without srvo (most Mk1 Fiestas had servos.
(2) Mk 3 Cortina 1300 without srvo (most M3 Cortinas had servos)
(3) Early VW Pollo or Golf 1100 without servo
(4) Triumph Spitfire 1500 duak circuit.
(5) Some FX4 Taxi models.
The bolt pattern for these cylinders is different ie the standard no servo pattern.
quote:
Originally posted by sebastiaan
The spacer was cut on the bandsaw at work at a 12 degree angle from a piece of large diameter bar. Then a suitable hole was machined to fit the M/C through (same diameter as the hole in the bulkhead, don't know the exact measurement. The spacer was then fitted between bulkhead and M/C with some longer bolts. It could be trimmed down further but I did not bother with that since I wanted to see if it worked first. I was lucky enough that I had enough spare length in my brake lines to not have to replace them.
Some pics...
brake spacer
brake spacer 2
brake spacer 3
brake spacer 4
brake spacer 5
Any pics of how much this moved the clevis down the pedal?
Has anyone else carried this out?
quote:m
Originally posted by rm0rgan
quote:
Originally posted by sebastiaan
The spacer was cut on the bandsaw at work at a 12 degree angle from a piece of large diameter bar. Then a suitable hole was machined to fit the M/C through (same diameter as the hole in the bulkhead, don't know the exact measurement. The spacer was then fitted between bulkhead and M/C with some longer bolts. It could be trimmed down further but I did not bother with that since I wanted to see if it worked first. I was lucky enough that I had enough spare length in my brake lines to not have to replace them.
Some pics...
Spot on! This is my next job....dont suppose you fancy making up a washer for me in return for a beer token! :-)