C15 brake master cylinder upgrade?

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Bsim9751
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C15 brake master cylinder upgrade?

Post by Bsim9751 »

Hi all. I’m looking to swap the brake master cylinder on my c15 for one that’ll move a bit more fluid. I’ve fitted bigger brakes and want to make best use of them. I read that on the 205, which shared many parts, swapping for a 406 non abs master cylinder is the way to go as it has 4 outputs but the c15 only has 2 outputs and, obviously, no abs. Anyone know of a decent upgrade? I hope that all makes sense.

Cheers!!

Bsim9751
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Re: C15 brake master cylinder upgrade?

Post by Bsim9751 »

Bump

Sorry

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white exec
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Re: C15 brake master cylinder upgrade?

Post by white exec »

What vehicle did the 'bigger brakes' come from or would be fitted to?
The master cylinder from that vehicle should work ok.
Just guesswork; sorry nothing more specific.

Also, C15 was essentially Visa (I think). Could that help?

wheeler
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Re: C15 brake master cylinder upgrade?

Post by wheeler »

Will be interesting to see the difference any changes make. I don't think I've ever driven any other vehicles with worse brakes than C15's.

Gibbo2286
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Re: C15 brake master cylinder upgrade?

Post by Gibbo2286 »

Should have tried the old cable Bendix or rod Girling Wheeler. :-D

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Paul-R
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Re: C15 brake master cylinder upgrade?

Post by Paul-R »

Not to mention the hydromechanical brakes on the A35. My very first car and they were diabolical.

wheeler
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Re: C15 brake master cylinder upgrade?

Post by wheeler »

Im too young to even know what any of those things above are :lol:

Bsim9751
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Re: C15 brake master cylinder upgrade?

Post by Bsim9751 »

Ok I don’t think I was asking the right question. The c15 brake master cylinder has 2 outputs, I guess one front and one rear? Could I use a master cylinder from a car with abs like the 306 gti6 that the brakes came from?

doctle
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Re: C15 brake master cylinder upgrade?

Post by doctle »

If you can fit the 4 outlet master cylinder you should be able to blank 2 off with bleed nipples?

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white exec
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Re: C15 brake master cylinder upgrade?

Post by white exec »

One problem with mix'n'matching brake master cylinders with brake caliper/shoe units can be the quantity of fluid which is delivered with each brake application. If the master cylinder delivers a quantity of fluid on each press of the pedal which is less than the wheel units require, then there is a risk that the pedal will get dangerously close to the floor before anything happens.

Further complicated if there is a vacuum servo between master cyl and wheels. The servo will require a certain dose of fluid for it to operate, and it in turn needs to satisfy the wheel units.

Was the reason I suggested trying to use the components from a production car, which are known compatible. I think the biggest risk is wheel cylinders which are too large for the master cylinder. You could always just take a chance, and if it works, fine.
_________

One other possibility - don't know whether you could do this on C15 (or whether it has one already) - is just to add a vacuum servo (could difficult on a diesel :( ) to the original kit. Did this successfully on a 1959 Mini, which had drums all round!

Gibbo2286
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Re: C15 brake master cylinder upgrade?

Post by Gibbo2286 »

I bought and sold a lot of C15 vans, never thought that the original brakes were any way inefficient for the needs, if they were properly maintained.

wheeler
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Re: C15 brake master cylinder upgrade?

Post by wheeler »

white exec wrote:
29 Apr 2020, 12:23
don't know whether you could do this on C15 (or whether it has one already) - is just to add a vacuum servo (could difficult on a diesel :( ) to the original kit.
Cant really say on the older ones but the post 2000 ones with the DW8 engine definitely had vacuum servo assisted brakes.