What kind of a proportioning valve do I need for a FJ80 master cyl. swap? (1 Viewer)

[Kamaro]

I just swapped in a FJ80 brake master cyl. and booster into my '79 FJ40 which has the stock front disc and rear drum brakes, but I'm not sure which proportioning valve do I need for this setup. I bought my truck as a project and all the brake components were either missing or rusted to death, and I got the FJ80 (non ABS type) for free so thats what I'm gonna use. I have searched the forum and I got mixed answers and all of the similar cases uses 4 wheel discs. Do I use a FJ80 valve? or perhaps FJ60? .

 

[Shark56]

I just used the stock proportioning valve and it has been working great for 5 years or so.

 

[Pighead]

First, I might determine if you really need a proportioning valve.

 

[Living in the Past]

The FJ80 in the US had rear drums in 91/92. The FZJ80 had four wheel disc brakes. The rear drum on the FJ80 uses one brake cylinder like the 8/80+ 40 series. I have FJ80 non ABS, early nineties 4Runner and 84 HJ47 with front disc booster/master cylinder setups I think should work fine with the later 8/80 axles I had. For my 76 have a spare booster from a 78.

 

[pjohnson]

Run it and see if you need one. Easy to plumb in later.
If you do, I suggest an adjustable version for flexibility.

 

[Shark56]

To go deeper into this.
I just swapped a front drum axle to a disk axle.
I set up booster and Master Cylinder, FJ80 type, just like my other that I been running for over 5 years.
After a couple drives I thought damn these brakes do not feel anything like my others.
Tested on some gravel and everything locked up at once. I thought I had everything set up the same. Then I realized I had forgotten to put on the Proportioning valve from the donnor 78.
Cleaned it up, hooked it up and so far a driveway test feels right.
Anyone know if the FJ80's had a rear proportioning valve like the later 40's do.
I'm betting you will need one.

 

[1911]

I used a generic aftermarket adjustable one from Wilwood.

IMG_1253[1].JPG

• 1911
• Mar 2, 2020

FZJ80 master cylinder & City Racer brake booster

 

[Kamaro]

Thank you guys for all the info, that was exactly what I was looking for. I happen to have a universal wilwood manual valve in the shop, I'm gonna install it and start from there. Thanks again!