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master cylinder
craig_thomas - 6/9/09 at 06:40 PM

which master cylinder is best to use with which resevoir as i have two.

speedyxjs - 6/9/09 at 06:44 PM

More info may be needed.

Welcome to the madhouse btw

craig_thomas - 6/9/09 at 06:50 PM

were runnung ford sierra calipers dront and rear

speedyxjs - 6/9/09 at 06:59 PM

Do you have the original sierra master cylinder as that will have the same bore size.

prawnabie - 6/9/09 at 07:05 PM

are you using the sierra pedalbox or have you bought one which requires a balance bar assembly?

Shaun

britishtrident - 6/9/09 at 07:07 PM

Buy a Fiesta Mk1 non-servo master cylinder off ebay it has a smaller bore than the Sierra cylinder and will give the a brake that won't require excessive driver effort to stop the car.

Master cylinders from cars with servos have much too large a bore for a car with short (low leverage ratio) pedals and no servo.

Caterham and Westfield both use 0.7" dia master cylinders

craig_thomas - 6/9/09 at 07:12 PM

the car has 2 master cylinders, but i have been told that this wont pass the IVA test, is this true. so i have the pedal box to have a split system

britishtrident - 6/9/09 at 07:39 PM

quote:
Originally posted by craig_thomas
the car has 2 master cylinders, but i have been told that this wont pass the IVA test, is this true. so i have the pedal box to have a split system


If you permanently lock the adjustment system (ie weld the lock nuts) it will pass IVA however you would need to find the right adjustment first and it isn't the best solution for a road car.

For a road car even if occaisionally used on the track a tandem master cylinder is the best solution.

prawnabie - 6/9/09 at 07:42 PM

By "wont pass IVA" I think he means the new rules they have on brake circuit failure.

I havent seen a solution to this yet, but TBH I haven't been looking!

Shaun

cd.thomson - 7/9/09 at 08:14 AM

according to Dax theres no "brake circuit failure" issues?

The only trouble with the dual circuit is the adjustable bias bar, which now needs to be welded and they've passed cars under IVA with this setup.

Again this information is from my kit manufacturer not from some realm of imagination in my own head.

MikeRJ - 7/9/09 at 08:39 AM

The issue is the IVA brake efficiency requirements under a single circuit failure were clearly made with a diagonally split braking system in mind, which is not compatible with a bias bar system.