i ahve a 1991 camaro rs.

I can get a rear out of a 1993 f-bdoy with disc brakes from a junk yard.

$250 rear end

$50 calipers set

$30 rotors set

First is this a good deal. And second what do i have do to to get the disc brakes to work on my car that orig had drums. What do i have to do to get the e-brake hooked up. And is there anything else i should be aware of that I have to change.

 

what you will need is a gm "j65" proprtioning valve for wheel wheel disc...mine went in no prob...i did have problems with that rear brakes leaking from the copper washers so after a few hours i just got fed up and brought it in
....with the this rear those zr1 rims wont need spacers from what i understand

 

$330 is a decent price for all of that.
My car came with disc in the rear already so I just hooked up my stock brake lines to the calipers.
One of my friends bought a complete 4th gen rear with disc brakes on it and it still had the brake lines on it. We took his rear off and disconnected his brake line from the Y connector on the center of his rear where they split to go to each drum. We then attached that one brake line to the Y on the 4th gen rear that he bought. He also bought an adjustable proportioning valve for his setup.

If the 4th gen rear had ABS and Traction control then there isn't going to be a Y connector on the rear because the ABS controls each of the 4 brakes independently.
The rear I got had ABS and Traction Control so that is why I used my stock brake lines to the calipers.

About the e-brake, I still haven't had a chance to mess with it but I read that 92 First Design ebrake cables bolt right up. I haven't had a chance to get one from the dealer to check it out for myself yet so don't order them unless you can return them if they don't work.
I am buying an LT1 motor and tranny in less than a week to replace my dead 305 so the e-brake isn't a concern at this moment since the car isn't running anymore.

When I get the e-brake figured out, I'll post it here.

 

You might want to check with www.speedautomotive.com They took their parts inventory down but they had complete rear ends for 250. You might want to drop them an email and ask what they mean by complete.

 

so ZEPHER,

hao orig had disc brakes before the swap. Did you keep you propotioning valve or did you get the 4th gen one. I plan on getting one from a 1991 with disc brakes to make things easier. Only $67 from GM. As appose to the $120 4th gen valve.

 

I used the prop valve that was already on my car. Seemed to work fine.

 

So i got the rear end:

question 1: what is the wire comming from the top center.

and

question 2: there is a hole with a plastic plug on the top. Is that all that is sappose to be in the hole, just a small plastic plug.

 

I want to swap in a fourth gen rear eventually, as well. If you get it from a junk yard, how do know if the gears are good? Or do you just put new gears in?

Also, don't you have to use spacers on all four corners of our cars (stock) to use most wheels? What do you do about the front so that you don't have to use spacers?

 

Wire at the top center could be the connection for the ABS and traction control. Look at the axles and see if there is 3" round gear looking thing sitting on the axle between the hub and the rear end housing. That is the gear that tells the computer if the tire is losing traction.

That small little plug on the top of the rear end is a vent, that is all that goes there.



If you want to run a 4th gen rear with 4th gen wheels, you will need spacers on the front. Only way to not use the spacers is to use 3rd gen wheels but then the rear wheels will stick out 2" on each side. If you can, special order some wheels like Torque Thrust II's, one pair for a 3rd gen offset and one pair for a 4th gen offset, then you won't need spacers, but you won't be able to rotate the wheels, you'll have to have the tires dismounted and rotated to the wheels.

 

What advantages does a 4th gen rear offer over the 3rd besides haveing disc brakes??

 

Only advantage is that you don't need spacers to run 4th gen wheels and if you get the brakes on them as well you'll have larger discs.

 

Quote:

What advantages does a 4th gen rear offer over the 3rd besides haveing disc brakes??

1. no rear spacer (big one for me, I got ZR1 wheels)

2. disk brakes

3. posi traction

4. 3.23 grears (i had 3.08)

---about the wire. I dont have the rear at my apt so i cant look at it right now, but I thought ABS came later. My rear end is from a 1993 Z28. Cout it be the spedomometer cable.

 

I fiqured out that the wire on the top is for the spedomometer.

Can i use the master cylinder and propotioning valve for drum bakes for a little while. Do i NEED to switch the master cylinder.

 

Are you sure that that connector is for the speedo?
Speedo signal comes from the tranny, not the rear.
I am almost 99% sure that is for ABS/Traction control.

I am not sure if using the stock drum prop valve will make the disc brakes lock up or not brake. If you do use it, just test out the car first to see how the brakes feel.

My friend went from drum to LT1 Disc rear and the next day while taking a turn his brakes locked up and he spun out, hit a curb, and broke one of the chrome 96 T/A wheels I sold him.

 

How much power can the 4th gen rears take compared to the stock 3rd gen 10 bolts?

Also, what size are the discs compared to the 3rd gens?

Thanks for the help.

Rob

 

Quote:

My friend went from drum to LT1 Disc rear and the next day while taking a turn his brakes locked up

Was he using the drum cylinder and valve set up?


Also, is the proportioning valve and combintion valve the same thing, or is proportioning valve inside the combination valve.

 

He had an adjustable prop valve. I am not sure about your other question though.

3rd gen and 4th gen rears are the same if they are 10 bolt, only 2 inches wider on each side.
The brakes are about an inch larger and the calipers are towards the rear on the 4th gen rears. On the 3rd gen rears, one caliper is on the frontside of the rotor and the other side is the opposite.

 

Weird, was there a reason for doing this?

Also, what about the posi units, were the 4th gen units stronger than the 3rd gens?

Thanks

Rob

 

I think on the 3rd gen, it was the same caliper for either side.
For the 4th gen, there is a left and a right specific caliper.

About the Posi, I have no idea, all I know is that an Aussie 9 bolt is stronger than a 10 bolt. I had the Aussie in my 86 Trans Am and didn't even know it till the guy I sold it to told me a few days later. We both thought it was a 10 bolt. I never bothered to count the diff cover bolts.

 

I just fiished swapping in a 97 rear in my 91z28. i went from drum to disc as well. i have not added a propotioing valve yet. the car does stop very well without it. one snag i hit though was the ebrake cables. i am using the cables from the 97 car. i got both ends to hook up but now need to figure out how they will hang in the brackets for the stock 3rd gen cables. i may either move the brackets on the underside of the floor or rig up something. anybody have this problem. the ebrake handle maxs out when pulled up.

 

I have that problem as well. Haven't had a chance to figure anything out yet.
If you rig up something that works, let us all know. I have a 5 speed and I need my e-brake.

Oh, and here is my LT1 motor,

 

Nice engine stand:sillylol:

As for the calipers on the 3rd gen rear, makes sense now that you mentioned they are the same.

Rob

 

That is the ghetto stand.

I hope to have my motor out and the new one in today.

 

Ya gotta open up those channels for the cables to sit in and put them in there and put that end of the sheath into that bracket and then use a hammer and a punch and pinch the end of the sheath into that bracket. It is hard to explain but once you get under there you will hopefully see what I am talking about.

I did the above method for getting the cables in the bracket and then used the threaded rod that the bracket goes on to back off the adjustment until the E-brake handle worked properly and the brakes weren't dragging on the rotors. My E-brake system works perfectly.

I also run 4th gen offset wheels and not having to get those spacers is a nice plus . So is the large (1LE for a 3rd gen) rear brakes . But I did the swap mainly for cheaper parts selection and a better gear ratio. It ended up being much cheaper to just get the 4th gen rear than getting gears and a new carrier for my B/W 9 bolt (it had 2.77 gears). I will yield that the 9 bolt is stronger than the 10 bolt I put in, but not enough for me to justify keeping the 9 bolt and dealing with all of its BS.

There is no difference in the strength of a thirdgen 10 bolt rear axle and a 4th gen 10 bolt unless one has 26 spline axles and one has 28 spline. Otherwise they are identical aside from ABS considerations and width. I am not sure off hand which years have what for splines.....

I had rear disc and am running the existing master cylinder and proportioning valve and it seems to work fine on the street. Some harder driving on a road course may reveal the need for a different brake bias so I am not sure if I will leave it as is or get an adjustable valve in the future.

I would think that the people with drum brakes will want to get a rear disc master cylinder and proportioning valve for the system to operate properly. The deal with the master cylinder is the reservoir size for a rear drum system will not provide enough fluid to compensate for the amount of fluid the calipers will demand when the pads wear down. This is not that huge of a deal if you just keep an eye on the fluid level and not let the rear portion get sucked dry. I also would think that the piston diameters are different for a rear disc versus a rear drum system since they usually are matched to the size of the pistons in calipers and wheel cylinders for optimal brake power. And the proportioning valve may not reveal that it needs to be replaced until you really push the brakes. But they are designed for specific applications and I am willing to bet that a properly matched system will outperform a mismatched one even if the mismatched one does in fact 'work'.

my $.02

Laterzzzzzzz,
Matt

 

so i got some roters. either the center hole on the roter is too small or the hub on the axle is too big. Whats the deal with that. I was just going to bring them back and get a differant brand, anybody know why this happened.

 

I am 99% sure that GM changed to a larger hub size starting in 1996. if the rotors you bought dont fit the take them back and get rotors for a 93-95 and see if that helps. if not then its time to enlarge those holes on the rotors

 

went to a differant store and got a differant brand and they worked fine. They were for a 1994 Z28. The hole has to be 2 3/4 inches or larger inorder to fit. the other ones were 1/8 to small.

 

So far i'm about 7 hrs into the swap. NO PROBLEMS. still have to hook up the drive shaft, calipers, brake lines, e-brake cables, and proprotioning valve. I hope the rest goes as easy. I will prob end up getting e-brake cables from GM for the 93 Z28. I will let everyone know.

 

so everthing is in except for the the e-brake cable. I bought 4th gen cables but when i went to put them in i noticed something. I dont have the ajustable "box" under the car for the cables. It goes from the handle to under the car. then it spits into the 2 cables to each wheel. Is anyboby else missing this adjustable peice. If i had it the 4th gen cables would fit. Now they are about 2 inches to short.

 

I was going to try and use an unshielded brake cable and attach each end to the 4th gen cables and then run it through the equalizer that is attached to the e-brake handle cable.

 

that basically what i found i was going to do. Just going to cplamp a cable from the hardware store to the e-brake cable, them to thr handle cable. Hope it works.

 

just wanted to let everyone know. IT IS DONE, NO PROBLEMS AT ALL.

 

Cool, now where are the pics and hardware list so we can get out E-Brakes working?

 

sorry no pics, didnt want to get the digital camera full of grease. The only thing that would need explaining is the e-brake. Everything else went in with no problem. To get the e-brake working I used 2 cables from a 4-th gen with disk and 2 cable claps. Since I didn't take pics I will draw them for you. (dont worry they wont look like crap). The only thing I want to make clear is I know it woked on my car, I cant say it is going to work on eveybody elses car. Dont get mad at me if it doesn't work. Also mar car doesn't have the e-break adjustment set up. So if you have it on your car you might have to do it a little differant. I will draw a pic and scan it soon. I will be happy to anwser any questions I can.

I'm out!!!

 

.

 

hope this helps a little

 

heres my parts list for the swap:

rear end with calipers (from junkyard)

set of brake pads

2 rotors

proportioning valve for disc brakes

2 4th gen e-brake cables

brake fluid

80-90W rear end grease

new sway bar bolts (the old ones WILL brake)

2 cable clamps (to hook up e-brake cables)

misc. bolts to hold everything together

 

so how much did it all end up costing?


Thanks,
Jesse

 

Just remember I did all this for my ZR1 wheels.

rear end with calipers (from junkyard) $300 (plus $50 core)

set of brake pads $40

2 rotors $35 peice

proportioning valve for disc brakes $60

2 4th gen e-brake cables $20 peice

brake fluid $2

80-90W rear end grease $3

new sway bar bolts (the old ones WILL brake) $6

2 cable clamps (to hook up e-brake cables) $1

misc. bolts to hold everything together $10

total..........................................................$532 plus tax

--plus--

Chrome ZR1 wheels and tires combo $1200

shipping for wheels $120

adaptors for front $160

locking lug nuts $20

(got chrome lugs for free with tires)

TOTAL.......................................................$2032

I think that is everything

 

you have the ebay id of the guy you got the wheels from? I have a feeling I know which one it is... Has a couple sets up for auction.

 

it was tires-and-parts

 

cool thanks... when we gonna see pics then huh? have the wheels on yet?

 

I have the rear wheels on, should get the adaptors tomorrow. I'll take pics as soon as the weather clears up. I live in minnesota, get this. Last tuesday we had a record high of 91 degrees, today it snowed.

 

Oh hay, I forgot to mention:

spedomometer gear (i went from 3.08 or 3.23 gears) $3

I didn't bother putting it in though. My spedo will only be off by 2.5 MPH

 

Maryland is like that... one day be in the 80s and then the next day it was hailing. Actually did that in one day once. It was weird. I cant take the cold. Maybe I need to move back to FL sometime. Been wanting to do the 4th gen rear swap for a while now... kills 3 birds with one stone. 3.42 gears, disc brakes, and no need for wheel spacers...

 

finally, here are the wheels

 

jawz: car is looking great. Saw it on the other post. What do you have planned next?

 

What worked for me is 1ST design 92 Camaro E-brake cables. part number 10164125. Worked perfectly with my 95 rear and 83 Camaro.

 

planned next: lowered and white face gauges

super83z, what do you mean by "1ST design 92 Camaro E-brake cables" are those from GM? my cables work but not the best. i can always go to something better.