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Discussion Starter #1 (Edited)
Hey guys...


My struggle to find OEM rear disc brake parts for the 9C1/SS has caused me to start researching other options. I am not looking for serious performance, I just want to replace my drums with functioning discs for a decent price. Hopefully some of the brake gurus can chime in.

First question:

Does anybody know if this kit would fit our cars? Aside from the bolt pattern, of course. It says it fits 1979 Caprice with 8.5" 10-bolt. https://www.summitracing.com/parts/sum-bk1623/applications/year/1979/model/caprice/axle-model/gm-8-5-in

Next:

I have been reading up on S10/Blazer rear brakes. Parts for these cars are super easy to find, both online and in the junkyard. If I am not mistaken, I think I can use backing plates from a 98-05 4WD S10/Blazer if I do one of two things. To use the 9c1/SS rotors, I would have to use a 0.50" spacer between the backing plate and axle housing. My other option would be to use the S10/Blazer rotors and get them drilled, etc. The calipers might even be interchangeable... can somebody confirm this? The one guy who I know of that used these brakes on a b-body rear axle used 2 passenger side 9c1 calipers, and I'm not sure why he did that.

Basically, I want to assemble a kit from the following parts:

98-05 S10/Blazer 4WD backing plates (88935985 and 88935986)
98-05 S10/Blazer rear calipers, brackets and pads
94-96 9C1/SS rear rotors

Then I would have a local shop make my 0.50" spacers.

Am I making sense here? I would love to hear from some of you guys that know more about this than me!

Thanks,

Matt
 

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Seems like a lot to go through only to find out the braking is mostly the same. Installing a residual pressure valve on rears,and keeping them adjusted go a long,long way in my opinion. That same money could easily be spent on things that make a bigger difference.
 

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Seems like a lot to go through only to find out the braking is mostly the same. Installing a residual pressure valve on rears,and keeping them adjusted go a long,long way in my opinion. That same money could easily be spent on things that make a bigger difference.
I have to agree here. I'm no expert on this but I did do some research in the past. I got all new rear brakes, drums, hardware, SS braided lines and the residual valve for less. Cost was not the consideration. Ease and performance was.

Mark: Snowman-33
 

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Discussion Starter #4
I was under the impression that converting to rear discs and performing the brake bolt mod would significantly improve my braking performance.
 

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Caddy-, offering subjective insights and comparisons of plain 'ol stock v. rear disc v. merely freshened up drums as on my current FWB. For the first year of my first FWB 19 years ago, I ran with pretty much unmolested usual rear brakes. Compared to my Impala SS it literally was all nosedives at every stop - and acted like infinitely variable braking depending on pedal pressure. Enter the rear disc conversion (Navy's scoop-to-nuts design). Replace nosedives with flat front/rear squat, and the pedal had little travel and felt either on or off. In combination with both bolt mods the car braked like a built sport compact. A 4,500# one lol



On my new FWB I decided just to optimize the rears and save for an eventual replay disc conversion. Like others here describe I went with all new drums, slaves, shoes, mounting hardware, full bleed DOT 5.1. Combined with only the back bolt mod and very close adjustment the brakes showed impressive improvement. I have to divulge that I went "all new" at the same time on the fronts too, so we don't have a pure experiment for the rears only. Overall it's not quite as flat as I recall rear discs, but then again that one had SS coils and Bilsteins, whereas my current one is running oem FE1 coils and Monroe SS. As it stands I'm going to follow up on that residual pressure valve, and I'm gonna wail on Mark for his lead with s.s. braided lines. Outside of that, come nicer weather I'll prep a spare front bolt with the mod and judge weather the change is worth being dammed to hell for doing it with drum rears. HTH
 

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While not a b-body did a rear disc swap on my jeep.
It uses the same rear shoes as a b-body and they weigh close to the same.
Honestly noticed very little improvement.
Fade is reduced but far as braking performance...meh.
 

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When I installed the limited slip diff in my S10, I swapped to larger wheel cylinders on the original drum brakes. The fronts still lockup first, but you can tell the rears are actually doing some of the work now. It's a cheap and easy way to get some more rear brake without making big modifications.
 

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Calling on Messrs 1slow96 and gbhs72,




Coming up blank here on specifics about the preferred residual pressure valve. Poking around I find several 10# options. Can you's confirm whether this is close? https://www.summitracing.com/parts/clp-rcv-10/overview/ What hose size do we have? And considering a FWB, and retaining ABS, do I need one for each rear wheel?


1slow-, I've caught your couple of past references to an adjustable proportioning valve, which also happens to be included in the description of at least one of the residual valves on Summit. Is it mandatory for use with a residual valve, or (as I joked above), is there merit in experimenting with the front (stealth/prop.) bolt mod to increase the rears from 5% to 10%? For ref I've already done the back (no delay) bolt mod. Sort of extraneous questions, I know. But most all I find on the residual valve revolves around commercial or racing apps.
 

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I installed a 10# residual pressure valve on my '98 C/K pickup w/drum brakes,and it did seem to help response,and improved brake system performance. Both my vehicles are ABS delete,and truck has an adjustable proportion valve on the rear brake circuit. Any issue with rears locking up prematurely can be easily dealt with by turning the knob.
 

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Calling on Messrs 1slow96 and gbhs72,
Bob, Sorry for the delay. Busy getting Hospice set up for my wife's aunt. We're bringing her home today. We refuse to put family in a nursing home. Here is the valve I got. https://www.jegs.com/i/JEGS/555/631031/10002/-1 For some reason I have usually bought from Jegs. I'm sure that the one you noted is good. It should only require you to splice in the valve with two new fittings. I'm doing the ABS delete so I only needed one valve. I'm not sure if you will need a second one. Oh yeah, The line size I bought is 1/4 inch.

Mark: Snowman-33
 

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Thanks Mark. Yah usually default to helping smaller scale operations whenever possible, but Jegs and Summit pretty much interchangeable. But I'll check both for avail./price when the choice is between them.


Keep the wheel straight as long as possible unless/until inevitably forced over to the nursing home route. I had to do that for an uncle I was close to. First - Visiting Nurse, then area Mennonites helped, then assisted care, then a full-care home. No matter how frequently the visits it was clear to catch him winding down in what turns out just a more cheerful and better decorated hospital room. At several $k/mo. it was a rather pricey path to the end of the line. Haha nothing quite like bringing the room down with our whining eh.
 

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1/4" is correct for rear. You only need the one valve which can go anywhere along the long run of brake line from the front to the back. Easiest to install where factory uses a coupler to join two lengths of line. Should be one,or two of those somewhere along it's length.
 

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Bob, thanks for the helpful words. Wife's aunt lives next door to us and my MIL is on the corner down from us. My wife is a retired nurse, daughter is a Paramedic, the lady next to wife's aunt is a nurse too (her friend). Me, I was a combat lifesaver in Desert Storm. We pretty well have it covered for now. With all these women to take care of I have a need for this forum to have guy talk.

I'm curious now if two valves would be needed with the ABS. Might be helpful for future questions on this mod.

Thanks too to all here for the information on our love affairs.

Mark: Snowman-33
 

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1/4" is correct for rear. You only need the one valve which can go anywhere along the long run of brake line from the front to the back. Easiest to install where factory uses a coupler to join two lengths of line. Should be one,or two of those somewhere along it's length.
Thanks for that info. Your answer about putting it inline should help others here. It's what I had planned on doing. I just haven't decided if I want it up front, might conduct some heat into brake fluid from exhaust heat, or further back.

Mark: Snowman-33
 

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1/4" is correct for rear. You only need the one valve which can go anywhere along the long run of brake line from the front to the back. Easiest to install where factory uses a coupler to join two lengths of line. Should be one,or two of those somewhere along it's length.

Thanks for the backup confirmation on size. I thought the TC using a 4-channel system (including reluctors at each rear wheel) is to partially/temporarily brake a slipping wheel to favor the one with better traction. I'll be scoping out the ABS module on both my cars and count for an added hardline going to the back, and will report back.
 

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These valves are not intended to be used w/ABS.
 

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..........Enter the rear disc conversion (Navy's scoop-to-nuts design). Replace nosedives with flat front/rear squat, and the pedal had little travel and felt either on or off. In combination with both bolt mods the car braked like a built sport compact. A 4,500# one lol ......
Any links or more info on the rear disc conversion or bolt mods?
 

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Why not use the "search" function? None of this is new,and few are likely to repost info that has been posted many,many times.
 

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