[HJones1313]

After a lot of research I decided to go ahead and do a rear disc conversion to my 70 GTO, 10 bolt non c-clip rearend, using a complete S10 setup. Everything fits and really looks as if it was built that way in 1970, except for one thing; there is some axle end play, due to extra thickness of the axle (caliper) bracket and backing plate. I've read that I need to shim the retainer plate to make it work - but how? Shim at the outside bearing face or at the inside face so the bearing is flush with the retainer? Any info would be appreciated

[Donovan]

You need to take up the space between the bearing retainer plate and the flange it bolts to. Like a sammich. Measure the Caliper bracket with a digital caliper or similar to get a precise number. Then measure the old drum backing plate. Subtract the number you got from the drum plate from the number you got from the caliper bracket and shim for that value. It will need to fit inside the axle shaft hole of the caliper bracket, obviously. The reason you subtract the value of the drum shield is because the bearing is a touch proud of the flange. Take the bracket off and reinsert the axle shaft you will see what I mean. Doing this as above you will restore the factory tolerance of the drum setup while having the disc setup.

Shim at the OUTSIDE bearing face.

What year S10 did you get the brakes from and what wheels are you using?

[HJones1313]

That makes total sense Donovan, I just wasn't sure that it could be done. Just finished doing a final fit this morning (minus shims), and it all fits perfectly (yes, the rotor turns lol). I got the setup off a '98 T15 Sonoma 4x4 Ext cab, and used new rotors for an '01 Blazer 2wd. I'm using 15 x 7 Rally II's, which fit, but need longer studs. The total so far, including rebuilt calipers, new pads and rotors, and new parking brake shoes, is only $208. Parking brake connections are the only thing left.
I've put a lot of work in this project, and have lots of notes and photos if anyone's interested - already made the mistakes for you.

[JackMonkey]

I would like some of the info you have gotten. I saw this swap in a magazine a few months ago. They used a couple of washers to shim the flange away from the backing plate. Real hi-tech stuff, huh? Other than that, the swap looked really nice.

[Scarebird]

I would not mind seeing a breakdown of this either...

Washers to shim? ugh.

[Old Goat 67]

I'll go one better. I really need to see this info, ASAP.
Would it be relevant to a 67 rear?

[Scarebird]

Use differential shims for this, they come in various thicknesses. I wonder if the C6/F body parking brake is the same as the S10 unit. I am trying to dope this out for a better rear package. The C6 backing plate is in several pieces- and may be able to mount to a bolt in BOP axle housing without shimming.

[Donovan]

Originally Posted by HJones1313

That makes total sense Donovan, I just wasn't sure that it could be done. Just finished doing a final fit this morning (minus shims), and it all fits perfectly (yes, the rotor turns lol). I got the setup off a '98 T15 Sonoma 4x4 Ext cab, and used new rotors for an '01 Blazer 2wd. I'm using 15 x 7 Rally II's, which fit, but need longer studs. The total so far, including rebuilt calipers, new pads and rotors, and new parking brake shoes, is only $208. Parking brake connections are the only thing left.
I've put a lot of work in this project, and have lots of notes and photos if anyone's interested - already made the mistakes for you.

HR! Great swap! I think it goes a long way for most folks especially wanting to retain stock 15" rims. I tried to do the same with LS1 brakes but they don't inset enough on the spindle. ( like Scarebird told me The S10 is a slightly smaller rotor, like 11.5" but has the same high quality aluminum calipers amd deeper inset to clear the rim face.

I've decided lately to go to a C3 brake system (JL8) for a stockish look

Please send me your pics, I love this stuff! BTW, what are the exact dimensions on the rotors front and back? Diameter and thickness..

Oh yeah another neat feature, the parking brake retainer is built into the caliper bracket, so you only have to adapt the other end to your stock cable pull.


Don't you get the Tall spindle conversion with this too? So you get s 2-fer

[HJones1313]

The S10 parking brake shoes are 7.5". I've already mic'd the S10 bracket which is .380", and the drum plate is .130'....1/4" difference to shim. If you want photos of the conversion just shoot me an e-mail address, I'm glad I can help

[HJones1313]

Guys, since there is interest, I have the same type of notes (but much shorter!) on my tall spindle/12" front rotor conversion using BMR tubular Upper and lower arms. As you may guess, I make these notes on everything I do to the car.

[brianberes]

PM sent. Thanks for the offer of help with this project!
Cheers to the greatest bunch of pontiac people.

[Northern Goat]

I actually cut the area that mounts to the axle tube from my old backing plate and used right stuff on both sides to seal. Worked great. There is an article in the June 2006 issue of HPP that I helped Don. With the exception of the 69 all the other pics are of the instal on my car. Let me know if I can help.

[Karch]

Scarebird,
I've got LS1 rear setup in a box. If you need dimensions...let me know.

[HJones1313]

Here's some pics guys.

[Old Goat 67]

Good morning Howard,
I see you have the picture posting down pat.
You have been a busy boy overnight. I think I am understanding things so far, except I am not clear in our conversation and the pics, as to where the parking brake set up is, but I guess it would become very clear when I get a donor vehicle in sight. Could you post pics of that as well? I am saving all info, as you would expect....
Thanks friend,
Charles

[Northern Goat]

The parking brake is a ring that sits within the dust sheild and actuates against the inside of the rotor. The mechanism to expand the ring is located on the bottom of the backing plate.

[Old Goat 67]

Any updates Howard? I, for one, would love to know.
Charles

[chuckmnv]

Howard -
I, too, would be interested in your entire setup - front and rear. Also interested in the front upper/lower A-arms. Please pm me.
Thanx,
cm

[GStage1]

I did the rear conversion using TSM products. Here is an article for it if you want to compare another set-up to the S10 set-up:

http://www.buickperformance.com/rrdisc.htm

[the450r]

this thread needs more info. i have the simular setup you do on a 68 rear axle with 02 s10 rears. my shims are in between the bearing and the bearing retainer. so axle goes through ebrake bracket axle with bearing retainer on outside of ebrake bracket. bolted in and rotor on and the caliper mount is almost into the rotor on the front (outside). and there is a good gap in the rear i dont think a pad would fall through it but maybe a really thin one could. how do u center the pads and caliper???? i think it would bolt together but the pad travel wouldnt be even which makes me wonder if i would run out of caliper travel on the slides or pop the piston out.
is this how you put yours together?

High Performance Pontiac did a write up on this and its horrible they dont shim anything and u can see in the picture that they put the bearing retainer on with no shims and bent it. they never mention pulling the bearings off and putting the s10 ebrake bracket on the axle then putting the retainer and bearings back on. because thats what they did from the picture.

http://www.highperformancepontiac.co...tallation.html
http://www.highperformancepontiac.co.../photo_10.html

maybe machine the caliper mount thinner? if the ebrake bracket was on the outside of the bearing retainer HPP style a thinner shim thickness would be needed to make up only the backing plate. this would bring the pads more in line but id probably destroy my new bearing taking it off again and somekind of shim would be needed to not bent the bearing retainer cutting the mounting flange out of the backing plate would work too. Like Northern Goat did.

help!!!