[Jason H]

Ok heres the deal: I went to a junk yard one day and found an 80 or 81 firebird which had rear discs. The bolt pattern for the backing plates to the housing is the same as the rear end in my 68 lemans, so I pulled them I took them home.
My problem is this: The calipers mount on different sides of each other. What I mean is on one side it is on the front side of the rotor and the other side it is on the back side of the rotor. Is this right? Shouldn't they mount so that the calipers are in the same place? If so should they be on the front or the back side of the rotor? Will the calipers being in different spots effect braking?

Here are some addresses of some pics that show the backing plates and calipers on a rearend. http://www.geocities.com/jasons6894/Picture001.jpg http://www.geocities.com/jasons6894/Picture002.jpg http://www.geocities.com/jasons6894/Picture003.jpg
(if the links don't work delete the file name of the pic and try it again. It sould show a list of files on my site, from there just click on one of the files.)

Thanks for you help
Jason

[This message has been edited by Jason H (edited 12-07-2001).]

[Jason H]

Ok heres the deal: I went to a junk yard one day and found an 80 or 81 firebird which had rear discs. The bolt pattern for the backing plates to the housing is the same as the rear end in my 68 lemans, so I pulled them I took them home.
My problem is this: The calipers mount on different sides of each other. What I mean is on one side it is on the front side of the rotor and the other side it is on the back side of the rotor. Is this right? Shouldn't they mount so that the calipers are in the same place? If so should they be on the front or the back side of the rotor? Will the calipers being in different spots effect braking?

Here are some addresses of some pics that show the backing plates and calipers on a rearend. http://www.geocities.com/jasons6894/Picture001.jpg http://www.geocities.com/jasons6894/Picture002.jpg http://www.geocities.com/jasons6894/Picture003.jpg
(if the links don't work delete the file name of the pic and try it again. It sould show a list of files on my site, from there just click on one of the files.)

Thanks for you help
Jason

[This message has been edited by Jason H (edited 12-07-2001).]

['ol Pinion head]

Jason,
Tore three more of these rearends apart today. They (calipers) are supposed to be on opposite sides, that is how they came. The late 70's J65 or WS6 (w/ J65) T/A's & Formula's were the best handling & stopping T/A's built to that time. Rear disc brakes hauled the car down from 70-0 in like 40 something extra feet & that was on mediocre 70 series tires.

The main times one needs to swap brackets around (actually use a different bracket) is when putting these caliper mounts on a 65-67 Chevelle 12 bolt, '67 monoleaf Bird, & 64-early 66 GTO. Parking brake cables get in the way of the shock mounts in these instances, & different brackets & cables have to be routed to remedy this. These disc brake pieces are harder to mount on the bolt in axle rearends due to centering the rotors. Ed from Washington state & I posted on this back in October or early November.

I'm working on a picture album of every popular GM rearend with this type of disc brakes mounted on it. On e-Bay, you'll see the dinky third gen Z28-T/A rear disc brackets. I don't use the 3rd Gen F-body rear brake pieces as their calipers are smaller & swept area (pad surface contact area)is not as large.

[Jason H]

So since Im using coil over shocks, which dont use the stock shock mounts, I should be able to use these brakes? All I really need to do is figure out the parking brake setup?

I knew these were a good find, even more so since I paid $100 (the junk yard wanted $170, but since I loaned my hammer to some guy he told his buddy behind the counter to give me a brake on the setup) for the backing plates, calipers, rotors, and parking brake cables.

Thanks
Jason

[Philcol]

Would he also have to use the longer axles like the T/A has or does this apply here?

Phil

[Half-Inch Stud]

I tried to install the 3rd Gen rear disc onto my 69 Bird 12Bolt. Silly fool I was because the caliper brackets cause the calipers to interfere with the 5-leaf stack.

I sought and found two sets of 70-81 rear disc caliper brackets. Got all the parts, so will revisit the rear disc someday...like when I have C-Clip eliminators and good axles.

thanks OPH for the install advice. Woinder if I'll remember that when time comes for Install?....yes I will.