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Discussion Starter · #1 ·
I am in the process of doing a sas on my 94 bronco and would like to go with the stock 79 bronco brake lines for the 44 in the front, necessitating all new plumbing.
If I run all new lines and bypass the 4wabs, will I need an adjustable proportioner if I am still running rear drums.
A little history, I replaced the master, booster and rear cylinders with F350 stuff, and noticed little if any gains. My 'theory' is that the 4wabs bottle necks everything and won't allow any better braking. I am sure my theory is prolly totally fubar, so can someone with the knowledge please set me straight?
thanks
 

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Discussion Starter · #5 ·
thank you for the links. I will look into it.
My braking has always seemed fairly inadequate, especially with the 35's now. I tried the upgrade several people have done, whcih involves swapping the booster and m/c (up from 1 1/16 to 1 1/8 IIRC) to the f350 stuff, and then larger diameter rear cylinders. I don't know how to do the calculations for this stuff, so I really can't answer that. While everyone with RABs and 'less' reports great braking increases, I feel that mine has gotten worse if anything. The 4wabs is an electronic device, that as I understand it, cycles little pistons or something inside the unit to keep the brakes from lockin up. There is no other prop valve that I can detect.
If anything, I would say that currently my rears do not work as well as they should, though they shoes, etc are all fairly new. So I would say I am front biased. With the sas, rotor and pad size stay the same. I found a good link on using thunderbird calipers (ford car really) that have a larger steel piston, that should greatly improve front braking, while keeping most everything else the same as stock 79 ford.
So if I do bypass this thing, will I need a prop valve if I am running a single line to the front and one to the rear(standard solid axle style that splits along the axle, instead of two seperate lines in the front and one in the rear, like I have now) if I am running rear drum brakes. From what I have found on the subject, it seems to me I may not?????
Thanks again for the help Ed.
 

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Discussion Starter · #9 ·
Originally posted by munkee
HOWEVER (this is a big misconception) if you DECREASE the size of the m/c piston you INCREASE the force at the rotor (assuming the caliper diameter stays the same).

Thank you for all the info. I will try and digest it all and check it against my vehicle. But based on the snipit of info above that you gave me, does that then mean that if I went from a 1 1/16 stock mc to a 1 1/8 f350 that I have then decreased my force at the rotors, and would that not then help explain why my braking is poor?
Would that contribute to high breake heat/fade, lending to my squishy brake pedal (though it seems equally squisher hot or cold)
I have been running with the abs fuse pulled for the last year, and noticed no effect at all on the braking. Is it possible that the larger rear wheel cylinders is the major culprit in the poor braking?

Thanks again Ed.
 

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Discussion Starter · #11 ·
no the 4wabs dont have the rabs. That is a good article about the tbird calipers, I have seen, but was going to hold off in the anticipation of a 8 lug, sterling swap in the near future. I like the simplicity of the solid 44 brake lines, and its non limiting factor for wheel travel if I should go to a coil over setup with the wristed arm I am going to use. Not sure the brake lines would be a factor, but figured I would only do this once.
I want to bypass the 4wabs due to the inability of bleeding the unit without some 1500 dollar tool from mother ford, and since it wont work with the sas, I figured ditch the bitch.
 

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Discussion Starter · #13 ·
yeah, it didn't last long under daves rig, but he is a lot of right foot where I am not.
The 44 came cheap with everything that swaps over from the ttb. Figured I would run this first, swap the e40d for a zf and then start going bigger next year.
our buddy with the chevy is also in the process of going to a 95 60 with radius arms, so well see.
Time and money!
 
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