Master cylinder bore size

I am planning to put a Ford Explorer 8.8 rear axle with drum brakes (10 x 2 1/2) and the TSM disc brake conversion on the front of my L-110, and hoping not to reinvent the wheel. Has anyone used that combination with manual brakes? I'm trying to determine the best master cylinder bore. Ideally, I'd like to use an AMC master cylinder, MC36456, as it is narrower than most, and has the plumbing on the engine side. It has a bore of 1 1/16, and I'm wondering if that's just too big. Any help or thoughts are appreciated.

Paul, I sent you a private message.

T
Columbia, Mo.

That AMC master cylinder is a disc/drum master. it may not send enough volume to the rear calipers.

https://www.tsmmfg.net/

"We supply complete kits, taking all the guesswork out of parts needed to complete installation."
Thie a copy and paste off the home page of tsm.

The axle I'm using is a '92, so has drum brakes in the rear.

I've looked well beyond the home page of TSM. They don't list a master cylinder, or have a recommendation that would be for other than either an IH rear axle and their disc front, or their disc front and disc rear on a Dana 44 in an R100. I know the usual recommendation from brake sites is to use a universal Corvette MC with a 1" bore, but geez that thing is wide.

https://www.mpbrakes.com/ If this were my project and I needed help, I would start phoning some of these businesses who specialize in this stuff.
Another thing you could try, is to research the master cylinder size Ford used on their disc/drum Explorers.
Drum brake cylinders always take more fluid to operate. Disc brake calipers use very little fluid on application. It is the fluid-mechanical advantages you need to get right. GM/Chevy trucks had disc-dram applications for many years. One of the pickup applications has to be close enough.
I am using a GMC disc/drum master on my L110/Cummins/4X4. The axles are not GM. This has nothing to do with matching brands. It is all matching hydraulic advantages.
Why not use the Ford or GM engineering? It is free.

I haven't been able to find manual brakes as an option on the Explorers, so that doesn't get me there. Trying to find a match, or close to it, between Ford or GM pickups, with whatever pedal ratio each had, and the 10 x 2 1/2" rear shoes on the Explorer and the Lincoln Mk VII rotors and Monte Carlo calipers of the TSM kit seems like a needle in a haystack proposition, but may be what it comes to. I was just hoping that someone on here might have previously used the same combination of rear axle and disc brake kit, and could, like Goldilocks, say whether their master cylinder left the pedal too spongy, too hard, or just right. Was worth a shot.

Matching a master cylinder to a system is not about power brakes or manual brakes. The amount to fluid the MS can move should closely match the requirement of the brake cylinders, whether disc or drum. If for some reason the power to the assist fails, the brakes become manual and are required to work.
It is time for you to do some research on your own. You could start by calling the company you bought your front disc system from. I am sure you are not the first person to use a Ford 8.8, disc or drum with an after-market front disc conversion.
You say, "I was just hoping that someone on here might have previously used the same combination of rear axle and disc brake kit, and could . . . . . "I did and I mentioned it. "I am using a GMC disc/drum master" with DANA axles that never were under a GM pickup.
A power assist for braking is just that, an assist. The power should reduce the amount of foot pressure the drive needs, nothing else. If a vehicle has brakes that underperform or fade, the brakes will be the same with power assist.
You have all of the information you need. Do something with it.
I had to figure this stuff out on my own. I took good engineering design and practices from what I saw in a Ford recycling business. My 1940 Ford has a Ford 8.8, disc brake differential and an aftermarket front disc brake kit. The master cylinder I chose is an Explorer unit with disc brakes. The power assist I chose is a BOSCH hydro-boost from a Thunderbird SC. My power steering is a GM Saginaw from a Chevy Malibu and the power steering pump is from a Lincoln TC.
The tilt steering column in the '40 Ford is a Saginaw from a 1977 Chevy Van. The steering wheel is a Lecarra. It is a collection of mindless dumb parts that need to be matched.
88

Folks in the world of AMC cars know a lot about what's required to go to/from power/manual brakes. They deal with a ton of parts made of Unobtanium.

Pedal ratio, once you have the right master cylinder, is what's important. If you're going from manual brakes to manual brakes, that's not a worry; IH did the engineering for you. [The AMC folks going from manual to power also have pushrod length to deal with; you won't have that worry.]

I think the master cylinder in the photo nikkinutshop posted might be EXACTLY what you're looking for, because the aluminum master body is narrow...

Early 70s Ford Torinos with manual disc/drum brakes used either a 1" or 15/16" bore, if that helps. I'm pretty sure the ports are outboard which may be a non-starter