What would be my easiest options into making this work?? I have a complete 4th gen donor car i could take lines, master, etc but looking to keep it simple as possible using orig 3rd gen parts!! Is there a way i can just tie both rear caliper lines into the single feed line already under my 91z third gen??

 

its a direct bolt in, the brakes lines on the 4th gen rear will bolt right to your stock flex line to the axle. Take everything, brakes, brake lines, parking brake cables and the entire parking brake assembly from the tunnel. It will save you from having to buy custom cables, but if you do go the custom route, ebmiller sells them His site is flynbye.

the 4th gen rear is wider.

 

the 4th gen rear is gutted in the means of drag no ebrake components just calipers and discs! so i probaly wont have ebrake nor really mind.. just weekend toy, , i wouldnt be trying to jurry rig in a diff year rear if it wasnt for the fact this 4th gen rear is a moeser 12 bolt with wolfe rear sway welded to it

my third gen car has the earls stainless line lil upgrade kit, at the rear theres one solid hardline that adapts to the earls stainless braid line, from there it goes to a lil dist block that bolted to the ten bolt, so i would be good to just plumb my disc brake lines right into that block?? no diff prop valve needed or anything??

 

Some people will tell you to swap the 4th gen proportioning valve out, some won't.

But since you already have it, you might as well.

 

im sure its just a slight diff in brake pressures, may not even be noticable to some?? iill have to eyeball the prop valves tomm and see how hairy it would be to swap, just a weekend toy.. doesnt have to be perfect.. just not locking rear tires under norm use or throwing me across center line and id be happy,

 

you mean the 4th gen master. Not the prop valve, i dont think the 4th gen prop valve is compatible with a 3rd gen. For that matter, i dont even know what it looks like, never seen one?

as for the OP and the parking brake, if you are using the t56, i would HIGHLY recommend hooking up the parking brake. I didnt have one for a while in my 86 and it was a bit of a PITA, ended up having the car roll away from me and cause several hundred dollars in damage because of the lack of a parking brake.

 

For best brake performance, I'd certainly change the proportioning valve (valves were designed to optimize specific systems: drum or disc). That said, if you're unconcerned about "perfect," then disregard the above--the car will still stop.

JamesC

 

cars an automatic it will have park brake, and yea im willing to give it a whirl with 3rd gen prop, valve. i did cacth a diference in brake lines from 3rd gen to 4th, two brake lines from drum to dist block all have small ends, 1 line off 4th gen caliper is small to a bigger nut, that bigger tube nut isnt going to bolt right to dist block, may be able to swap a line off the third gen rear or just pick up a new small - small tube nut line,

 

Does your state require the e-brake at inspection time? Mine does, even for automatics.

 

wouldnt matter even if it did ;}

 

How can you tell if an 99+ rear end has a auburn unit or Zexsel unit? Is there something written on the housing or do you just have to open up the cover and look?

 

It depends on the year, 89+ have the right proportional valve, and shouldn't be changed.

 

Addressed (somewhat) in the following link:

https://www.thirdgen.org/forums/brak...nal-valve.html

JamesC

 

https://www.thirdgen.org/forums/brak...air-101-a.html

Just picked thru this and I think I gonna change the prop. valve just to be on the safe side. My brakes work fine but I dont want to play around with brakes. Is it possible that a newer prop. valve will work cuz I think its going to be a PITA to find a 90-92 valve.