R-985

Wow. Now *That's* an engine! No wonder it stuck in your memory.
The closest I got was a 4x6cyl radial - https://en.wikipedia.org/wiki/File:Pratt_&_Whitney_R-4360_Wasp_Major_1.jpg
https://en.wikipedia.org/wiki/File:Pratt_&_Whitney_R-4360_Wasp_Major_1.jpg

They had an early V12 DeHavallind on a stand. 'Earned a rebuke for getting a shot inside a cordoned area. Sigh. and had film back issues & didn't get the shot.

You have mighty fine taste in motive force.

My Gargoyling tripped over some YouTube stuff -- including some bloke down under who assembled one of those R-895s from old parts to the point it runs! And here's your R-4360! Takes a stiff upper lip to be hanging that close to a monster like that on a trailer. And that 4360 was 4 x 7 cylinders -- Throckmortons Law of Perversity or something, radials are always an odd number of cylinders per row. YouTube is scary -- have been known to stay up until 2 or 3 AM more than once going from one to the next, to the next ....
As in something big enough to climb on
And Coolspring is out in the western end of the state, one of these days I gotta get there when they run this gas compressor -- whatta piece of hardware! Double acting cylinders burn natural gas at one end, compress the stuff into the lines at the other. There's one of those in running condition out in Minnesota also. Needless to say, they don't drag them to festivals on a trailer!

DWT, those are a scream. Boy toy candy of the first order. The amount of time & work for that radial resto beggars the imagination. I think it was the honorable ColColt that mentioned doing a body-off, frame-up resto of a 60's musclecar. A local friend does classic Triumph motorcycles to concours specs (drool-worthy). I'm always amazed at what happens when imagination, curiosity and willingness to get dirty come together. Thank You for posting!