(at about 1:00;00 and 18:00 into the film) When the scarf girl comes out to start the race, the amount of grease on her upper body changes. In longer shots, it is a thick coat almost completely obscuring her breasts, but in close-ups, it is almost completely wiped off and her breasts are fully exposed.
The car to be won in the final Death Match is originally a stripped-out 3rd generation F-body, but after the unveiling, it is changed to a modern late model 5th generation Camaro.
(at about 7:00 into the film) When Goldberg is playing cards, his hand shows that he is carrying three Jacks and two Nines. In poker terminology, this would be considered a full house: Jacks over Nines or Jacks full of Nines. However, when he plays the hand, one of the other players comments "Nines over Jacks."
(at about 1:00:00 and 5:00 into the film) When Connor Gibson is at Jane's house/living space after he has won a chance at the Death Race, they are talking about a 1970 Stingray Corvette. However, when Gibson is giving the specs of his old Corvette, he says "Holley and Rochester Quadrajet Carb". The original LT-1 engine had a Holley Carburetor. You cannot have a Quadrajet Carburetor if you have a Holley and vice versa. It is either one or the other.
(at about 2:00 into the film) In the pre-credits race, an opponent fires a rocket-propelled grenade at Frankenstein, only to see it make a sudden 90-degree turn away from Frankenstein's car. While a jamming system could cause this with a guided missile, a rocker-propelled grenade has no guidance system.
(at about 50:00 into the film) During the Death Pit fight, the Butcher hits Gibson in the face several times with the head of his sledgehammer. Although Gibson spits out some blood, he suffers no damage to his nose or any other visible damage to his face.
(at about 2:00 into the film) A car is blown off a bridge (by a grenade launcher). As it falls, you can clearly see cables that ensure it falls in the right spot and manner.
Frankenstein's loudmouth stripper girlfriend might notice Frank is not all he used to be at the end of the film.
(at about 1:00;00 and 15:00 into the film) When Lists is identifying the racers of the Death Race on the broadcast, he lists them all by name except for racer Dirk, who he identifies by his vehicle, War Cycle.