brake proportioning valve WTF is it ?

[splitbusvanatic]

Im thinking I need a brake proportioning valve
I don't know much only that it would prevent too much brake pressure going to my rear drums (I have 944 front discs)
And also in turn lessen the chance of rear wheels locking before fronts.
(I think)

So what type of brake proportioning valve would be best to use ?
If any.
Bear mind.
I've 944 Servo & MC.
Front 944 Discs and Calipers.
Rear Drums off a T25.

Thanks in Advance.
( this brake stuff is a head scratcher )

[richbaker78]

you are right in saying that you need one...and in some ways its more important in a van as the loads are more likely to vary.

.there are a couple of options:
The original one which is basic but not always effective as it relys on the vans relative level front to back - in reality the insides get gunged up and thus most dont actually funtion as proportiuoning valves at all.

A manual one (from demon tweeks or similar) which can be expensive and you basically dial in what you want front ad back (worked out on trial and error basis) these are mostly fitted to race/rally cars although i have fitted one as any other type of proportioning valve could potentially be confused by my air suspension.

Or you can use one which uses a lever off a rear suspension point - these are fitted to many cars VW Polos use a very simple one which measures how much the rear sinks down under load - the compression of the suspension moves the lever and proportions brakes accordingly.

[Superleggo]

I was giving this some thought as well the polo one sounds interesting. I guess it would take some trial and error to get it right.

I had the smae problem on my mini moke as they are so light at the back. In the end I drilled the back out of a mini unit to make the spring pressure adjustable to stop it locking up.

What do most people do about split line brake systems on Campers. Do they split the brake lines front ot back or corner to corner. If corner to corner I assume two valves are needed. Any neat solutions?

[richbaker78]

split brake systems on campers are done back and front on campers.

Not sure how you would proportion a diagonal split system - two valves I guess as you say!