Vacuum brake replacement parts advice

BennyBuick

Member
Joined
Sep 10, 2014
The brakes in the GN I just bought have failed. It had been converted to vacuum brakes, at least that is what the previous owner said, but that was way before even he owned the car. Anyways, I lost most all the braking and pedal went to floor. Fluid was almost all gone in MC. Filled it up to get home but pedal is quite squishy. Master is leaking around flange where it connects to booster. Also, it appears that the calipers are leaking as well. Going to replace MC and calipers. Maybe replace the booster as well, but if it looks goods upon further inspection I may not go thru the trouble. So, question is. .. what to but for MC and calipers. Upgrade time? Well, I'm not dropping the money on a set of baers, but I've heard a set of calipers for say a 95 s10 would upgrade me from single piston to dual and are compatible. Confirmation or thoughts anyone? Also, should i get MC from g body or b body? Does it matter? What can I buy for a small improvement? Thanks guys
 
Well you can buy the Master cylinder anywhere but it's always good practice to support one of our vendors!! As for the brake calipers your gonna have to buy stock one cause unless you have the spindle and hub off the blazer the dual piston will not work. Another option is SSBC sells a dual piston aluminum caliper that mounts on to the stock spindle just be prepared to pay $$$ for them. IMO replace the stock calipers and master cylinder do the brake booster too since you have it out. Buy a set of Russell SS brake hoses. They will give you very good stopping power over the cheap factory rubber hoses.
 
Well you can buy the Master cylinder anywhere but it's always good practice to support one of our vendors!! As for the brake calipers your gonna have to buy stock one cause unless you have the spindle and hub off the blazer the dual piston will not work. Another option is SSBC sells a dual piston aluminum caliper that mounts on to the stock spindle just be prepared to pay $$$ for them. IMO replace the stock calipers and master cylinder do the brake booster too since you have it out. Buy a set of Russell SS brake hoses. They will give you very good stopping power over the cheap factory rubber hoses.

Car already has SS brake lines. SSBC dual piston calipers about $550, hmm tempting. stock would be much cheaper though no doubt. I would like to buy from a vendor here, but I want them tomorrow to start this project. I'd like to be done by Friday night so unfortunately that is going to restrict me to a local parts store. I like Oreilly but there is a NAPA super close to me. we also have auto zone or advance auto parts or all the regular chain stores. If I need the spindle and hub to do s10 calipers I'll just forget about it. I would like to do the upgraded booster though from a 1990 caprice to get the dual 10.75" diaphragm booster.
 
Ordered MC / booster from 1990 caprice that has 10.75" dual diaphragms $117 @ O'reillys and 2 stock replacement calipers $20 each. Lol. Wow that's cheap. Same MC / booster at NAPA was $150. Both prices were after core charge. SSBCs look nice and would be nice upgrade, but that's an incredible cost difference. I wonder how much better the 4 piston Baer calipers are vs 2 piston SSBC. Baer setup is like $$1600 vs. about $600 for SSBC roughly. I won't be looking into it now because of cost after I just bought the car, but may consider upgrade down the road if stockers turn out to be less than adequate which I know they will be. $20 for each caliper is too good to pass up to get me safely back on the road... For now anyhow. Thanks TRICKSIXPA for saving me more work and trips to auto store. Glad I know now that hub and spindle is requirement for those S10 calipers. Too bad, would have been a nice cheap upgrade, but I'm just not ready for the extra work and money for hub and spindles and I don't want to go junkyard shopping. If it was direct bolt on fit I would have definitely done it just to upgrade to dual piston. Thanks again
 
I just bought the same booster from Summitt Racing for $81.97 (+ $12.00 core charge).
It's listed for a 1990 Chev Caprice - 10 3/4" Dual Diaphragm Brake Booster

Cardone Industries 54-71040 Power Brake Booster

Summitt Part # AAZ-54-71040
 
Did it come with the MC or was it booster only? Mine was combo. It's all installed and pedal feel is great although I still have it on jack stands. Will report back after test drive. Calipers were not needed as the problem was a faulty steel braided line. By faulty, I mean installed incorrectly and thus damaged fitting and stressed the crimp end. Everything is bled and ready.
 
Did it come with the MC or was it booster only? Mine was combo. It's all installed and pedal feel is great although I still have it on jack stands. Will report back after test drive. Calipers were not needed as the problem was a faulty steel braided line. By faulty, I mean installed incorrectly and thus damaged fitting and stressed the crimp end. Everything is bled and ready.



It was for the brake booster only.
 
I just did this very same install. IMO the 10.75 booster gives too much assist. It's way to easy to lock the brakes now. Pedal does feel great, and it doesn't take much effort (foot pressure) to stop the car, but in a quick apply situation, you may find yourself flat spotting your fronts. Will be even more touchy in the wet.
 
just got home from test drive and it is a nice upgrade. I don't find it gives too much assist, it feels sure and firm, but I can feather it just as well as I could before and lockup isn't a problem nor does it occur too easily for me. I'm quite happy with the way it turned out. I'd be even happier if I had put beefier calipers on front but maybe someday. All in all, installation is a success, properly bled and I'm very pleased. I would recommend this booster upgrade for anyone. MC from the caprice seems like it doesn't quite have enough clearance for the hood liner to not make a smidge of contact with the MC cover. Not an issue at all, just an observation. Good to go.
 
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