Adjustable Break prop valve?
 

Hey guys wondering if you guys have ran a adjustable prop valve On a s4 fc? It's a gxl. My front lines weren't bleeding . Figured out my prob valve wasn't allowing fluid into the front lines . Couldn't find a oem replacment anywhere so figured screw it do it this way. But curious to how it went for people!? Thanks anything appreciated !

The front brake lines do not go through the prop valve. Only the rear brake line does.

If you want to run a prop valve, the Flyin Miata kit is what you want. I run it on my car, it works great but you will make sure it is adjusted correctly.


https://flyinmiata.com/index.php?dep...umber=14-76240

The front lines do run threw the valve ? I have the peice sitting in front of me. There is a line that pushing fluid from master to prop valve. Then One line runs to the rears and 1 to each of the front calipers How do I send pictures ? On mobile ? Lol

Here you go this is the one I just took out new one should be in today.

The front right brake line does go through the valve. It is a separate port from the rear, and is just a pass through.

The FM kit just has a union to connect both front lines together directly.

I have a 929 master, but this is how mine is set up with the prop valve.

Attachment 635401

yeah, the front line is just a pass-through.

Do you have ABS or no?

Oh I see . Damn my valve isn't here until Tuesday. If the one I got doesn't work I'll go with that setup you have there. My stock valve was screwed . Wasn't letting fluid to either of the front lines . So that master your running has 2 outlets off the master ? The stock one only has one? Sorry confused kinda

I think I just realized my master cylinder is pooched . Sigh lol it all makes sence now

Yep.. If you aren't getting fluid to the front brakes, the prop valve has nothing to do with your problem.

Where might I find that master cylinder ? You just used all stock lines ? Thanks

His master cylinder (and mine) are from a Mazda 929. it's slightly larger than the S5 TII master cylinder.

normal FC: 7/8"
S5 TII and FD: 15/16"
929: 1"

you need to replace the brake booster too if you go from a 7/8" to something else, they're not compatible.

Also, if you're running with no ABS, you'll need a "Y" fitting like you can see on the front of it.

https://lh4.googleusercontent.com/-A...0/IMAG3625.jpg

Haha, you did copy mine didn't you?

Here is mine..it will look familiar to the above.

Attachment 635265

You can order a factory replacement master cylinder from RockAuto.com

As Eage8 stated we both have 929 master cylinder and booster which changes plumbing a bit. The factory replacement MC will drop in.

Booste3Rex,

The stock prop valve you showed is a prop valve for the rear, but it is also a shuttle valve that keeps half the system working if the other half gets a leak. If you blow a hose in the front the valve guts will slide to the front preventing flow to that side and allowing you to still use the rear brakes without draining the fluid through the leaking front half. The opposite happens if the rear half leaks. What probably happened is that you pressed on the brake pedal with no pressure in the front side. It has happened to me a number of times when changing brake hydraulic parts. It can be a real pain to get the valve reset. Usually you can get it reset by pumping the crap out of the brake pedal. I have also used air pressure.

The valve is actually called a combination valve, since it does proportioning and also shuts off half the system in the event of a leak. Wilwood makes an adjustable combination valve that allows you to retain the function of the shuttle valve and still add adjustability to your rear brakes.

Yeah, but it has the wrong thread pitch on the lines so you'll need to get probably hard to find adapters... the same adapters from the flying miata kit won't work either.

You definitely need to adapt something. If you have a tubing flare tool, you can cut off the metric flare nut and install an SAE nut. I think it is 3/8 x 24 INF, or something like that. In any case, the same size tubing works with both the metric and SAE flare nut.

does anyone have schematics for this? what year/engine of 929 are we talking about and is it non abs? i want to get rid of the abs pump on s5 t2. do i have to install an aftermarket proportioning valve alos or i can do it with 929/ non abs rx7 master cylinder?

Non ABS if you can, but it really does not matter much. The only real difference in the fittings between ABS and non ABS.

Mine is off of a 93.. that generation 929 is the one you want.

So basically i can use my existing brake cylinder what is totally working and just buy the wilwood proportional valve and hook it up like on these pictures?

To run the 929 master you want to run it with an FD or 929 booster. Running the stock bore FC master with the other booster defeats the purpose.

If you are not making brake caliper changes you can run the stock FC prop valve with the new booster and MC.

If you just want an adjustable prop valve with everything you have now, buy the flyin miata kit. It is easier to install with the FC MC than it is with the 929 MC.

I just want te get rid of abs, im okay with the brakes fof now, im not looking to buy new parts, just to buy enough to get it work right. Thanks for the info.

Mazdatrix sells an "abs pump delete kit". That's really all you need:
Master Cylinders + Brake Parts

the stock proportioning valve will work fine.

thank you for the information!
i think im gonna buy the wilwood prop valve because i can get it locally and they make it in metric in/outlets also :)

The metric willwood valve is a 10mmx1 bubble flare which isn't right... mazda uses inverted flares. it won't work without re-flaring the lines.

it also doesn't help get rid of the abs at all. it just takes the place of the stock unit which is already there and works fine. I'm not sure what you think this valve is going to do to get rid of the ABS...

How much do rear brakes work with the stock prop valve?
My friend has a flairing tool i can use.