I'm watching Back to the Future III, this evening, and the critical hurdle was that they couldn't figure out a way to get a Delorean up to 88 mph. They tried alcohol, but it blew the manifold off the engine, rendering it useless.
I won't give away their solution (spoiler), but would like to open this thread for Back to the Future aficionados so we can discuss alternative methods of propelling a DeLorean to 88 mph in ways available in 1885.
(by the way, aficionado is the correct spelling, as it's a modern Spanish word, as is patio, even though most English-speaking people spell it afficionado).
First, we must remember that the DeLorean that went to 1885 was the one with the Mr. Fusion, could fly, etc. However, the lightening strike that sent it there fried the time circuits and the car's flying ability.
There was one hilarious and highly improbably scene in the movie where they were pulling it behind a 6-horse team, but since horses top out around 40 mph, less than half that required for DeLorean time travel, it was improbable that they would have ever tried that in the first place... ( and they only reported 35 mph in the movie...)
I thought of a method involving ropes, a very heavy weight and a cliff (particularly, a mesa, plentiful in the old West - and the new!)
Attach one end of the rope to a fixed location. Attach the other to a heavy weight next to the edge of the mesa, with a line draw between the fixed point and the edge perpendicular to the edge of the mesa. The DeLorean is drawn back such that perhaps it's three times distant from that perpendicular line than between the fixed point and the heavy weight, and with equal amounts of rope between it and both the fixed point and the weight. In addition, there's a (for lack of a better term) sort of capstan around which the length of rope between the DeLorean and the weight is fed such that the pulling point remains on a line between the pulling point and the fixed point that's perpendicular to the velocity vector of the DeLorean
It is such that the DeLorean's velocity vector is parallel to the edge of the mesa (not over it, as some might have thought - remember, the fusion and the flying circuits have been fried).
Then, simply drop the weight off the cliff. It is pulled by gravity, building velocity. As the rope between the pulling point shortens due to the falling weight, it drags the DeLorean along, at first with a large authority of the weight (potential energy), then, as the rope bend angle nears zero, transferring the falling weight's kinetic energy into even more tug.
I feel quite certain that if this system is properly designed, with enough rope to handle the strain, a suitable location, properly calculated weight, etc., it would have no trouble whatsoever of accelerating the DeLorean to 88 mph (or much further).
That's my solution.
I'd like to hear your solutions!