Brake booster upgrade

[JWestfall]

There are so many posts on this it just confused me. I have a 71 Wagoneer and the booster went out. I want to upgrade to a dual diaphragm without replacing the m/c or modifying anything else. Which part # or model year is my best bet that will fit in the right space. Thanks

[devildog80]

My $.02

Replace with stock parts, as they fit best, and lasted 51 years

[tgreese]

Mmm. I doubt you will be able to find the original equipment replacement for a '71, much less an upgrade that bolts in. These are oddball cars and production was low compared to popular brands like Ford and Chevy, especially in these pre-AMC years. A '71 is a Kaiser Wagoneer with an AMC engine. I expect you will need to send your existing booster to a rebuilder; there are no cores to rebuild for that early a year.

The later vehicles (post-1980) can use the J20 booster which is dual diaphragm, as I recall. There was a watershed change in 1974 for these vehicles (first major AMC upgrade), and again in 1980. Many, many changes at each of these watershed years.

Possible you could find a new hot rod booster, made for custom applications, that could be adapted to your existing brackets and pedals. Nothing that will just bolt in ... https://www.summitracing.com/search/par ... rsal%3Ayes

[Stuka]

You can get a factory style booster for a '71 from Napa (and most auto parts stores I would suspect): https://www.napaonline.com/en/p/NBB5473560

Though they are out of stock online. But you can check your local outlet. And call around to other parts houses.

As far as upgrades go, that will require some work to find a dual diaphragm that would fit a '71.

[Yeller]

A direct bolt in, no but close. A booster from a 1980 corvette will bolt up to the bracket. A push rod will need to be fabricated. The master cylinder will need to be replaced, but there are several available that will work, or you can purchase a pushrod insert to bolt the original up. Changing updating the original will be a good idea, the brake switch on the bottom is notorious for not working and leaking. It is very simple to fab a bracket to relocate that to the steering column.

[tgreese]

A booster like this is a little more expensive than the reman Corvette booster, but it's meant for universal application.
https://www.summitracing.com/parts/sum-760167

The firewall pattern looks close to the original booster, and they offer a kit to adapt the pedal linkage to the booster. It also has an adjustable master cylinder pushrod. If that's not workable, the page suggests some Wilwood master cylinders and a Corvette master cylinder that can be used with the booster.

[Yeller]

No need for a reman. Rockauto has a new one for $68. Been my go to for a vacuum booster for several years. The summit one works just as well with the same level of fab work.

[JWestfall]

Thanks for all the help. I'm going to try the Summit racing option because all the remanufactured ones are out of stock at this time.

[tgreese]

Maybe you realize this, but there are places that rebuild these boosters. These can be mass-market rebuilders that serve the parts store trade, or boutique rebuilders that serve the classic car owners.

These rebuilders will not list the boosters for sale if there are not enough cores available to stock them.

You can have your booster rebuilt. It will be easy for one of these boutique shops. Look online - https://www.bing.com/search?q=brake+booster+rebuilder

Can't be more specific since you have not put your location in your profile or signature. There is a place in your profile for this information, and it will appear with every post.

I'd also mention - I suspect an upgraded booster would not do much for you. You already have a brake booster, and these are drum brakes that will fade, even if you apply more force to the linings. If you want an upgrade, you could drill the drums (old race car tech) or upgrade the front axle to disks. Lots of information about the disk upgrade here and elsewhere online.

[Kowpie]

Not sure if you are interested at this point but maybe this helps add to the conversation for future questions. I recently had my original (1973 J4600) booster rebuilt by Power Brake Booster Exchange.

Power Brake Booster Exchange Inc
17820 Highway 99, Unit C
Lynnwood, WA 98037
503-238-8882
boostersteve@yahoo.com

Cost was $200.00 plus shipping. This was important to me as I'm looking to keep the vehicle as original as possible. They were excellent to deal with and did a wonderful job on the rebuild. Mine was painted but they do offer zinc plating as an option. Great folks to deal with and were fairly quick on the turn-around.
Cheers!

[JWestfall]

Finished the install with the universal booster from Summit and I couldn’t be happier. Much better braking and a little more room under the hood. Minor mods to the bracket (made the mounting holes a little bigger) and had to lengthen the m/c and pedal rods on the booster. Here are the parts I ordered from Summit: Wilwood Pedal Assembly Components 330-12897, Summit Racing™ Brake Pedal Rod Extension Kits SUM-760125, Summit Racing™ Power Brake Boosters SUM-760167.

[tgreese]

With the Wilwood part going around the post on the pedal, what did you use the extension kit for?

[JWestfall]

I still needed to extend the rod a little, so I cut way down the 3/8-24 threaded rod from the extension kit. If I was to do it again I would get some threaded rod from the hardware store and save a little $

[Remi]

For anyone looking for boosters in the future, BJ's Offroad in WA has several on their website. They specialize in FSJ parts and have great service. I've dealt with them several times and have no complaints.