Power brake booster upgrade

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Yeller
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Power brake booster upgrade

Post by Yeller » Tue May 04, 2021 7:04 pm

I figured before I reinvent the wheel and adapt a larger dual diaphragm brake booster for my 70 j2500 I’d ask y’all what you’re thoughts or recommendations are before I order parts and fab up linkage to adapt something. I’m even up for hydro boost, just seeing what has been done and possibly save some work.

Thanks in advance
Steve
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.


jhartings
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Re: Power brake booster upgrade

Post by jhartings » Wed May 05, 2021 3:36 pm

I did a Hydroboost with this guys help on my 69 Wagoneer and I love it.

http://www.custompowerbrake.com/

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Yeller
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Re: Power brake booster upgrade

Post by Yeller » Wed May 05, 2021 5:33 pm

Thanks for the info
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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tgreese
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Re: Power brake booster upgrade

Post by tgreese » Thu May 06, 2021 5:25 am

I recall the later booster for a Grand Wagoneer or J20 is dual diaphragm? Before you think about adapting something, I suggest you search old posts. There may be a factory equipment dual diaphragm that bolts in. Even if it's a little different, get friendly with your local old-time parts store and ask them to order one for you to look at. They may have a "20% restocking blah blah blah" policy, but if you are a good customer, they should do that for you. They do it all the time for their repair trade customers, and it does not cost them anything to send stuff back.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 FCA Jeep Cherokee KL Trailhawk, ECO Green
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rocklaurence
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Re: Power brake booster upgrade

Post by rocklaurence » Thu May 06, 2021 6:10 am

tgreese wrote:
Thu May 06, 2021 5:25 am
I recall the later booster for a Grand Wagoneer or J20 is dual diaphragm? Before you think about adapting something, I suggest you search old posts. There may be a factory equipment dual diaphragm that bolts in. Even if it's a little different, get friendly with your local old-time parts store and ask them to order one for you to look at. They may have a "20% restocking blah blah blah" policy, but if you are a good customer, they should do that for you. They do it all the time for their repair trade customers, and it does not cost them anything to send stuff back.
Yes, go this route. Ive never had issues with the Daul booster, Disc brake setups.


89_Wagon
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Re: Power brake booster upgrade

Post by 89_Wagon » Thu May 06, 2021 9:58 am

My 89 came with the dual diaphragm booster. I converted to hydroboost. Hydroboost is loads better IMO. Brakes require far less input. But, more $ and complexity.

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Yeller
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Re: Power brake booster upgrade

Post by Yeller » Thu May 06, 2021 2:52 pm

Really looking at hydro boost. Need to go to the picknpull and get a booster off a later model truck and see what I can do. I’ve installed it on customer vehicles but we bought them a kit that basically bolts on. I’m too cheap and doing it myself with a used unit it’s about the same cost as buying a vacuum booster. I’ll be sure to document what I come up with. Currently with the old single diaphragm booster it stops really good with little effort just cruising around but when you really need it to stop in a hurry it needs more boost, both feet aren’t enough lol
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.


rocklaurence
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Re: Power brake booster upgrade

Post by rocklaurence » Fri May 07, 2021 5:28 am

The Chevy Calipers and JB7 pads are also a nice improvement.


89_Wagon
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Re: Power brake booster upgrade

Post by 89_Wagon » Fri May 07, 2021 6:02 am

Are those drop in with stock rotors?

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tgreese
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Re: Power brake booster upgrade

Post by tgreese » Fri May 07, 2021 6:17 am

I would point out that the 11"x2" drum brakes may be the weak link here, not the booster. They will fade. Drilling the drums was race-car tech from the day.

Never mind - read your old posts and apparently you have a front disk conversion of some type. Disks are not self-energizing like drums, and the existing booster may be inadequate. CJ owners with through-the-floor pedals often go front disk with manual brakes. In that case, soft organic pads make the braking effort less.

An Astro Van is a common source for junkyard hydroboost.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 FCA Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.


itselliott
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Re: Power brake booster upgrade

Post by itselliott » Fri May 07, 2021 6:49 am

I also did the Hydroboost along with rear disc conversion using Cadillac Eldorado calipers...'76 I think...On my '78 J20. Fantastic braking.

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Stuka
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Re: Power brake booster upgrade

Post by Stuka » Fri May 07, 2021 11:13 am

Personally, I would go dual diaphragm over hydroboost mostly for the reliability and simplicity. Its not quite bolt in for a 1970, but its pretty close. You would also need the master cylinder matched for it. Plus the rod going from the brake pedal would need to be different. And I know you converted to disc, but make sure you also have the correct proportioning valve for front disc brakes.
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Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ


rocklaurence
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Re: Power brake booster upgrade

Post by rocklaurence » Fri May 07, 2021 12:14 pm

89_Wagon wrote:
Fri May 07, 2021 6:02 am
Are those drop in with stock rotors?

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Yes, the caliper is the same with the exception of the piston. Its approx 20% larger and the JB7 pads have approx' 25% more surface area. Theres plenty of writeups on the upgrade.

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Yeller
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Re: Power brake booster upgrade

Post by Yeller » Fri May 07, 2021 8:06 pm

Thank you everyone. I appreciate your responses. for myself I normally do a dual diaphragm booster but typically I’m also running a assist on the steering and have witnessed flow issues with that and hydro boost. No assist going on this truck, no front locker and smallish (for me anyway) 33” tires so really no need for it

As part of my disc swap I did install a tuff stuff proportioning valve for disc/drum. I did use the large Chevy calipers. Also used Ford F-150 hubs/rotors to keep 5x5.5 wheels. The disc set up doesn’t work with axles shafts on the closed knuckle front but it’s going to get replaced with a later j10 front housing that I picked up this week and it will all direct carry over to that without any issues. I knew that was the plan and I why I didn’t mess with adding the cj style discs. I also installed a 1-1/8” bore master cylinder to properly supply those big calipers with the correct amount of fluid volume to keep the pedal high and tight instead of low and scary. I’ll put all of this info in one thread soon.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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Yeller
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Location: Rogers County Oklahoma

Re: Power brake booster upgrade

Post by Yeller » Sat May 29, 2021 12:39 pm

I got hydroboost added today. Picked up a booster off of a 2005 Chevy diesel, was a very simple conversion. It comes with a plate that booted it to the firewall. Drilled holes in that plate and original booster bracket, lengthened the push rod 1/2” and bolted it up. Brakes are fantastic.
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The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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Yeller
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Location: Rogers County Oklahoma

Re: Power brake booster upgrade

Post by Yeller » Sat May 29, 2021 12:42 pm

I got hydroboost added today. Picked up a booster off of a 2005 Chevy diesel, was a very simple conversion. It comes with a plate that booted it to the firewall. Drilled holes in that plate and original booster bracket, lengthened the push rod 1/2” and bolted it up. Brakes are fantastic.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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Topic author
Yeller
Posts: 67
Joined: Thu Apr 01, 2021 7:54 am
Location: Rogers County Oklahoma

Re: Power brake booster upgrade

Post by Yeller » Sat May 29, 2021 12:44 pm

I got hydroboost added today. Picked up a booster off of a 2005 Chevy diesel, was a very simple conversion. It comes with a plate that booted it to the firewall. Drilled holes in that plate and original booster bracket, lengthened the push rod 1/2” and bolted it up. Brakes are fantastic.
You do not have the required permissions to view the files attached to this post.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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Topic author
Yeller
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Location: Rogers County Oklahoma

Re: Power brake booster upgrade

Post by Yeller » Sat May 29, 2021 12:46 pm

:oops: Double post is weird, only clicked submit once
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

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