Great Scott! DeLoreans Only Go to 85 Miles Per Hour!
Here’s a fascinating bit of movie trivia: if you tour the 'Hollywood Dream Machines' exhibit at the Petersen Automotive Museum and take a close look at the screen-used ‘Back to the Future’ DeLorean, you’ll notice that a sticker is covering the car’s original speedometer gauge. What is it hiding? The fact that DeLoreans only go to 85 miles per hour!
Needless to say, this was an easy fix for the props team to address, but a fun little tidbit to know considering how pivotal it is to the overall plot of the film that the car have the ability to get up to 88 miles per hour.
What’s more, the fact that this car and most others from the era were limited to 85 miles per hour is rooted in a bit of political history. Per Wikipedia:
On September 1, 1979 in a regulation that also regulated speedometer and odometer accuracy, the National Highway Traffic Safety Administration (NHTSA) required speedometers to have special emphasis on the number 55 and a maximum speed of 85mph (140km/h). Some manufacturers circumvented the rule by including extra lines beyond 85 to show higher speeds. However, on October 22, 1981, NHTSA proposed eliminating speedometer and odometer rules because they were "unlikely to yield significant safety benefits" and "[a] highlighted '55' on a speedometer scale adds little to the information provided to the driver by a roadside speed limit sign.