# Back to the Future III - alternate 88 mph methods **URL:** \ **Category:** Cafe Society\ **Created:** [October 31, 2003, 9:18pm UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728 "2003-10-31T21:18:58Z")\ **Posts on this page:** 17\ **Page:** 2
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [November 1, 2003, 4:36am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/21 "2003-11-01T04:36:15Z")
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. ---
**Author:** ![Ranchoth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ranchoth/32/1066_2.png) [@Ranchoth](https://boards.straightdope.com/u/Ranchoth)\ **Post date:** [November 1, 2003, 5:11am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/22 "2003-11-01T05:11:12Z")
> [@](#): > > \*Originally posted by friedo \* > \*\*NIf they dug up the DeLorean that Doc hid, then Marty would not have found it in 1955, and would have never gone back to 1885 to star in BTTF 3. > > Time travel paradoxes are fun. \*\* 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. ---
**Author:** ![Earl\_of\_the\_CC](https://avatars.discourse-cdn.com/v4/letter/e/58956e/32.png) [@Earl\_of\_the\_CC](https://boards.straightdope.com/u/Earl_of_the_CC)\ **Post date:** [November 1, 2003, 5:34am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/23 "2003-11-01T05:34:37Z")
> [@](#): > > \*Originally posted by criminalcatalog \* > \*\*That wouldn’t make the wheels spin, or the speedometer needle rise, which was how the car time-travelled. > > Mechanical Engineers: could my roller idea be applicated, or is 88pmh too much to ask for? \*\* 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… ---
**Author:** ![Morelin](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Morelin](https://boards.straightdope.com/u/Morelin)\ **Post date:** [November 1, 2003, 5:51am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/24 "2003-11-01T05:51:41Z")
erm, wasn’t the speedometer digital? Otherwise, how would you know you were going precisely 88 mph? ---
**Author:** ![Mikahw](https://avatars.discourse-cdn.com/v4/letter/m/e9bcb4/32.png) [@Mikahw](https://boards.straightdope.com/u/Mikahw)\ **Post date:** [November 1, 2003, 5:55am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/25 "2003-11-01T05:55:47Z")
> [@](#): > > But since by that point it hovered and ran off of garbage (Mr. Fusion) I don’t see the need for gas at all. That was just kind of gleaned over in the movie. It’s been a while since I saw the movie, but I do remember doc saying something about that. Ah, found it. > [@](#): > > Marty: Yeah, no big deal, we got Mr Fusion, right? > > Doc: Mr Fusion powers the time circuits and the flux capacitor. But the internal combustion engine runs on ordinary gasoline, it always has. There’s not going to be a gas station around here until sometime in the next century. Without gasoline, we can’t get the DeLorean up to 88 miles per hour. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 1, 2003, 5:58am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/26 "2003-11-01T05:58:43Z")
> [@](#): > > \*Originally posted by Ranchoth \* > \*\*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. \*\* _Both_ DeLoreans are broken. 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. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 1, 2003, 6:01am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/27 "2003-11-01T06:01:16Z")
> [@](#): > > \*Originally posted by friedo \* > \*\*He hides the DeLorean in the mine and sends Marty the letter telling him to get 1955-Doc to help him fix it. 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. ---
**Author:** ![vandal](https://avatars.discourse-cdn.com/v4/letter/v/858c86/32.png) [@vandal](https://boards.straightdope.com/u/vandal)\ **Post date:** [November 1, 2003, 6:08am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/28 "2003-11-01T06:08:55Z")
> [@](#): > > \*Originally posted by Morelin \* > \*\*erm, wasn’t the speedometer digital? Otherwise, how would you know you were going precisely 88 mph? \*\* No, the speedometer was analog. According to Doc, all the car needed to do was _reach_ 88 mph. (You didn’t actually need to _stay_ at 88 mph, if that’s what you getting at.) Once the car reaches that 88 mph speed, the flux capacitor and the time circuits do their thing, and time travel commences. ---
**Author:** ![Mikahw](https://avatars.discourse-cdn.com/v4/letter/m/e9bcb4/32.png) [@Mikahw](https://boards.straightdope.com/u/Mikahw)\ **Post date:** [November 1, 2003, 6:15am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/29 "2003-11-01T06:15:20Z")
> [@](#): > > No, the speedometer was analog. 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. ---
**Author:** ![vandal](https://avatars.discourse-cdn.com/v4/letter/v/858c86/32.png) [@vandal](https://boards.straightdope.com/u/vandal)\ **Post date:** [November 1, 2003, 6:18am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/30 "2003-11-01T06:18:44Z")
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. ---
**Author:** ![vandal](https://avatars.discourse-cdn.com/v4/letter/v/858c86/32.png) [@vandal](https://boards.straightdope.com/u/vandal)\ **Post date:** [November 1, 2003, 6:23am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/31 "2003-11-01T06:23:33Z")
> [@](#): > > \*Originally posted by Mikahw \* > \*\*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. \*\* Actually, you’re right. I was just thinking of the stock speedometer. ---
**Author:** ![Protesilaus](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Protesilaus](https://boards.straightdope.com/u/Protesilaus)\ **Post date:** [November 1, 2003, 6:30am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/32 "2003-11-01T06:30:11Z")
> [@](#): > > \*Originally posted by Chicago Faucet \* > **But since by that point it hovered and ran off of garbage (Mr. Fusion) I don’t see the need for gas at all. That was just kind of gleaned over in the movie.** 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. ---
**Author:** ![Protesilaus](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Protesilaus](https://boards.straightdope.com/u/Protesilaus)\ **Post date:** [November 1, 2003, 6:32am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/33 "2003-11-01T06:32:49Z")
35 minutes? Man, I _really_ should have previewed. ---
**Author:** ![Mikahw](https://avatars.discourse-cdn.com/v4/letter/m/e9bcb4/32.png) [@Mikahw](https://boards.straightdope.com/u/Mikahw)\ **Post date:** [November 1, 2003, 6:35am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/34 "2003-11-01T06:35:44Z")
😛 ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [November 1, 2003, 8:38am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/35 "2003-11-01T08:38:29Z")
> [@](#): > > \*Originally posted by friedo \* > \*\*_Both_ DeLoreans are broken. > > 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. \*\* 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! ---
**Author:** ![Futile\_Gesture](https://avatars.discourse-cdn.com/v4/letter/f/f05b48/32.png) [@Futile\_Gesture](https://boards.straightdope.com/u/Futile_Gesture)\ **Post date:** [November 1, 2003, 11:58am UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/36 "2003-11-01T11:58:58Z")
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. ---
**Author:** ![Gyrate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gyrate/32/3588_2.png) [@Gyrate](https://boards.straightdope.com/u/Gyrate)\ **Post date:** [November 1, 2003, 12:32pm UTC](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728/37 "2003-11-01T12:32:18Z")
> [@](#): > > \*Originally posted by Futile Gesture \* > \*\*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). \*\* 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. 😉 [Previous page](https://boards.straightdope.com/t/back-to-the-future-iii-alternate-88-mph-methods/210728.md?page=1)