WJ Master Upgrade

[blondejoncherokee]

So I have the WJ booster and master, but with the thunderbird calipers on the Bronco 44 front the pedal is pretty soft. Just wondering if anyone has done the WJ booster and master swap and then swapped in a 1 1/16 or 1 1/8 MC ?

 

[VAhasnoWAVES]

another option:
http://www.greatlakes4x4.com/showpost.php?p=3226208&postcount=110

 

[blondejoncherokee]

I've already researched that to death. the 2500 MC is 1.25 I think its way too big for my setup . I picked up 2 boosters today for fun from pnp, a 95 and a 96. I figure for 25$ each I grabbed the 2 they had. Ill try the dodge 2500 MC , 1 1/4, and the durango with the 1 1/8 and just see which one works better

 

[cal]

soft pedal is normal with the WJ master/booster.

you still stop fine, it just feels plush. part of swapping brakes over from a 'luxury' car.

 

[blondejoncherokee]

I don't know if I can get used to it wanting to travel more. Its been bled like crazy, threw 2 different brand new, non-reman MCs, same sort of pedal feel. I found roberts thread from 2007 about the same thing but no info in the thread on if he upgrade the MC or not. All the threads on Xj booster/MC combos pirate are great , but don't address the WJ booster it seems. It does stop good with 36s, but I want a more immediate feeling response.

I am thinking of ordering a dodge van 2500 MC just to see how it works with the 96 booster.

sometimes it seems like the pedal travels too far or I have to pump it almost . the T bird calipers are big- 3.1 single piston. From what I've read its more or the same volume as a 1 ton caliper with good sized dual piston calipers . with the WJ brakes when I had a 30 in it, it was fine, stopped with the 36s on a dime.

works great in 4 lo though .

Pretty sure the mid to late 70s t birds ran either a 1" MC or a 1 1/8 with hydroboost which leads to want to run a 1 1/8 MC.

I've bled the brakes so many times.

 

[Wiggleworm]

This is what the bronco guys are doing when they upgrade to the "thunderbird" brakes. http://fullsizebronco.com/forum/showthread.php?t=2551&highlight=brakes Post 6 gives you the part # for master/booster combination. From there you should be able to track down what size piston the MC has. Gets you one step closer to a solution. Im looking into something similar and came across it last night in my internet meanderings.

 

[blondejoncherokee]

link doesn't work.

 

[blondejoncherokee]

Yes that article claims to want to use a 1 1/16 Bore master and to remove the oring in the proportioning valve to let the fronts come on sooner. which makes sense. I think I will do the prop valve mod first then start looking into 1 1/16 to 1 1/8 MCs. Sounds like a plan for the 8.8 rear calipers/tbird front calipers.

this one works:
http://www.ford-trucks.com/article/...rake_Upgrade_for_1978__1979_Ford_Broncos.html

 

[XJLI]

i had a spongy pedal with my WJ setup in my 93 too... stock 30 brakes up front and the big drums on a XJ44 out back. stopped pretty good though.

 

[Talyn]

Everything I can find says the WJ's master is the same bore as the XJ's. I tried the WK booster and master on my XJ. A little different pedal feel, but thats about it.