Factual error: As everyone races through Illinois, notice the very large mountains. Illinois is a very flat state.
Factual error: Supposedly the Pantera was rigged to explode once it reached 160 mph. There are two problems here. First, a stock Detomaso Pantera could never reach 160, especially a smog-controlled "L" model with the old bias-ply Arriva tires, which is what they used in the movie. Second, the Dodge Polara police car that was tailing him closely and matching his speed, most DEFINITELY would not be able to achieve that speed.
Factual error: When Richard Kiel is shooting at Gene Wilder on the train, you hear the "ping" of a "silencer" on the gun. However, Kiel is shooting a .357 magnum, which cannot be equipped with a silencer.
Factual error: At the start of the movie, the nuclear-powered articulated bus that is attempting a non-stop land run to Denver leaves New York City, but you can see the Rocky Mountains in the background.
Factual error: Cagey Joe's pullover definitely looks more 1976 than 1926.
Factual error: When the lady wrestler falls out of the ring she lands on front row seats, pro wrestling doesn't allow chairs that close and there's no barricade there either.
Factual error: Several times during the film Sid and Tim talk of taking learner drivers out at the same time. This would be difficult as their driving school only has one car.
Factual error: The panels on a caravan are made of fibreglass so when Bob crashes his car into the caravan it wouldn't do as much damage as it did to Bob's car.