luke2152

Hey guys - building a kit car with mx5 components and I'm trying to remember how to connect the lines from the master cylinder to the proportioning valve (I'm assuming thats what the other unit alongside the MC does) and onto the front and rear brakes. There are 3 outlets on master cylinder and 2 inlets/2 outlets on proportioning valve.

Anyone care to have a look and help with a photo, a diagram or a good description.
Cheers,
Luke.

Edit - by the way mk1 1.8 with no abs

Braineack

iTrader: (62)

front two go to the front brakes, the one on the side goes to the rears.

luke2152

Thanks but my stock proportioning valve is a little different to your adjustable. Heres a pic. Pretty obvious what side the rear line goes through. I'm guessing one of the front lines goes through the other side of the proportioning valve to feed the rear in the event of a pressure drop. And the other front line goes straight from MC to caliper. Anyone confirm this?

Braineack

iTrader: (62)

ignore the picture and the prop valve and focus on: front two [ports off the master] go to the front brakes, the one on the side goes to the rears.


your prop valve question: the ports labeled F (for front) on your prop valve are completely straight through.

You should be able to imagine the picture I posted to look just like your oem prop valve... chop off the **** and duct tape the separated fitting to the valve...and it's identical.

Savington

iTrader: (31)

It's pretty simple, honestly. There are two ports labeled "F" - those are just connected together and that line runs to the RF caliper.

The rear lines run through the other two ports (labled with arrows), and the fluid flows in the direction the arrows point.

luke2152

Cheers guys this is how I've done it....it just seems strange to me that one front goes straight to the caliper and one goes through the proportioning valve...seems like it could unbalance the front?

NiklasFalk

iTrader: (1)

The prop valve on Mazdas shelf looks like that.
If one of the front lines goes through the straight-through side or not does not matter (it has absolutely no hydraulic function).
You can route the front line(s) without going through the "prop valve" if you want to.

What makes you think that a stock nonadjustable prop valve would be suitable for your goals?

luke2152

Part of the legalities of getting it on road here says it can't have an adjustable prop valve. Once its been through that test I can do what I like
But as for having no hydraulic function - it appears to have a drilling between the front and rear chambers which I'm guessing is to allow one side to feed the other in the event of one side failing.

NiklasFalk

iTrader: (1)

You can also plug one port in the MC and Tee the front brakes after the "prop valve" to make the routing a bit nicer (less to explain when someone will inspect it).

If the two circuits would have connections between them the working one would be worse when the other fails.
If the prop valve use pressure from the fronts for regulation I don't know (if that's the case it would be beneficial to still have the front using that side).

luke2152

Well as long as I've done it same as stock that will do for now anyway!

Braineack

iTrader: (62)

Both front lines goes directly to the caliper. The rear line go through a proportioning valve and it's split to both calipers in the rear.

I don't see the issue...

Leafy

iTrader: (1)

No on the stock prop valve the RF goes through the prop valve as a pressure reference.