I'm aware that 1970 and down Hemi MCs were taller and higher capacity than 440s, 383s, etc. Even the 1970 Hemi Air Grabber cars had a hole cut into the air box for clearance, but I can't find anything on the 1971 Hemi cars. Did they also receive a special MC?

Yes.

Look at RamMan for more info.

therammaninc.com

Yes, 70-71 disc brake hemi cars had a unique master cylinder. Chrysler part number 2944476 with Bendix casting number 2229191 on the bottom.
It looks like the ‘70 E body only disc brake part, except it’s 1-1/8” bore, different casting number and has a piston retaining bolt on the bottom of the casting.

IIRC there's 2 versions of this casting, one with lines inboard (facing engine) the other with lines outboard, HEMI application is lines outboard

No the B body 67-70 style with the taller thinner style casting is what you are thinking of. The outlets outboard version is casting 2225621 and is found on all disc 67 B bodies, 68-69 hemi B bodies, and 70 disc C bodies ( under several different Chrysler part numbers and perhaps some slight piston length differences, though they are all 1-1/8 bores).
The same style except lines exiting toward engine is casting number 2226821 and was used on 68-70 B bodies disc except hemi, again several Chrysler part numbers with slight piston length variations.
Hemi 70-71 disc is casting 2229191 and has a lower wider casting, although like the previously described B body disc masters has a “thermometer” style front of casting.
The part numbers, casting numbers and photographs of the different styles is documented in the Pulitzer Prize winning 2005 article pumping points in Mopar Action, if you have a copy of it in your old magazine stash.
http://www.moparts.org/Tech/MoparAction/Next/history/april2005.html

Thanks for all the posts. Master340 - I might actually have that article in my stash.

I'm going to guess we're talking about your 71 Runner? Survivor photos for reference.

The blue car and red car have aftermarket replacement master cylinders installed, the green car has a correct 2229191.

Easily distinguishable I would assume, because the 'thermometer' at the front of the masters has the divot on the blue and red car and the green car does not.

I use to have a used 1971 hemi master cylinder. No idea what happened to it as I know I didnt bring it with me on the cross country move. But dont remember getting rid of it either.
They are shorter and wider than the 70 version.

The 2 aftermarket MCs shown have what I’d call a nose or a snout. The OEM MC has feature that resembles a thermometer.
I’ve never seen an original Bendix master cylinder from that era with a divot in its nose, obviously there was a difference in how Bendix fixtured their castings during machining and how the aftermarket manufacturers did it.
Anytime you look under the hood of a vintage Mopar and see a master cylinder with that divot, you know it’s an aftermarket part.

this one is a little easier to see without the black paint

As Brad mentioned.....divot here seen on left aftermarket no divot on factory original on right.

Here's Brads Pultizer award winning Mopar Action article on master cylinders.....excellent , informative write-up

http://www.moparts.org/Tech/MoparAction/Master_Cylinder.pdf

Assembly line is painted black, so not a survivor without paint too.

Dragon - Were the master cylinders, MC cap, booster and booster valve painted as one assembly (bolts, gaskets, etc.) or were they painted black separately and bolted together later?

As a complete assy with the booster

the divot is from a center drill used to form a referencing point for a live center, used when machining the master cylinder bore.

I would take a divot MC over what I have now.