Well, having never seen BTTF2 on DVD and being unfamilar with the commentary, I have to say the “circumference velocity” argument sounds like hooey. If the DeLorean was instantly spun up to 88mph, Doc Brown (riding the DeLorean at the time) would have been squished like a frog in a centrifuge.
I suppose the Flux Capacitor has an inertial dampener, too.
Seems to me it would have been easier to just dump the 88mph requirement and say that on Brown’s first trip to the future (at the end of the first movie) he acquired a non-88 method in addition to Mr. Fusion; a method that could be triggered by an unexpected lightning strike. Then just make up some other reason why the DeLorean gets trapped in 1885.
Not so much of a problem…they could have just left the BROKEN DeLorean (from 1955) in the mine, in the place of the first one. They could leave a note explaining what was wrong with it, for 1955 Doc to repair when he and Marty dig it up.
Are you sure about this? Is it stated in the movie? If not, I seriously doubt this. You could just remove the glass covering the speedometer and shove the needle for one thing. And why would tire rotation matter? It’s not like they’re using the tire energy, they had nuclear power for that.
Of course, if they say that in the movie somewhere, no arguing with Doc Brown…
The one that is struck by lightning sends Doc back to 1885. The lightning destroys some imprtant time-travel parts that are irreplaceable in the 19th century, so Doc is stuck there. He hides the DeLorean in the mine and sends Marty the letter telling him to get 1955-Doc to help him fix it. They do so, and Marty takes it back to 1885. But he snags the fuel line, and so it’s broken again, since there’s no refined gasoline around.
So, in 1885, they have the broken DeLorean which won’t work at all due to the lightning strike, and the broken DeLorean which works fine except there’s no fuel.
Ergo, the only choice is to find some other means of propulsion for the one DeLorean which can still time travel.
I forgot to mention: the reason Doc sends the letter telling Marty where the time machine is and how to fix it is not so Marty can save Doc from Buford (Doc was obviously unaware of his fate) but that so Marty could go back to 1985.
I seem to recall there being two speedos. There was an analog one in the dash (goes all the way up to a whopping 85MPH, IIRC), as well as a digital one on top of the dash.
Oh, and regarding the OP, I think the way they did it in the movie was probably the best way, under the circumstances.
Achernar pretty much summed it up. They had three days to come up with and implement a plan. So, refining gasoline in the barn or finding a steep enough hill that also happens to have a railroad track really becomes an issue, since they’re pressed for time.
Mr. Fusion was just used to create the 1.21 gigawatts they’d otherwise need plutonium (or lightning) for. It powered the time circuits, not the Delorean’s engine.
You get the one with the good engine from the mine and swap the broken time travel thingy with the working one from the other car (which has the broken engine). You now have one car which has a good engine and a good time travel device. You also have one with a busted engine and a busted time travel device. You put the busted car in the mine with instructions on how to fix everything wrong with it. These instructions should also mention that Marty should store a couple of cans of gasoline in the trunk. Problem solved!
88mph is just a result of the engine imparting a required amount of kinetic energy to the vehicle, where it came from is irrelevant. So it’s not the engine, or the wheels, or the speedometer that count. The first two are just a means to an end, and the latter is just a passive instrument to measure speed.
Thus, pushing the car off a high-enough cliff would work just as well, (supposing the terminal velocity of a falling DeLorean is fast enough). Or finding a long and steep enough slope.
Except for the small problem that you’d still be falling at 88+ mph when you reached 1985. I’m not sure dying in a fiery smash in 1985 is any improvement over dying in a fiery smash in 1885. But apart from that, it sounds like a good plan.