Revealing mistake: Just after the Buick spins around to knock the trailer loose, we see the Buick speeding away backwards alongside the truck. If you look carefully you can see the REAR tires are steering, not the fronts. This car was modified with the body mounted backwards on the chassis because the transmission only has one reverse gear, so to get the speed and handling needed, the car had to be going 'forward' with a 'backward' body. (00:05:30)
Revealing mistake: When Dom and Brian are racing for the job, there is one point where Brian is seen skidding around a corner. There are already skid marks in the exact place Brian skids.
Revealing mistake: When Paul Walker's Subaru is flipped over by the Torino after emerging from the mine, the propeller shaft linking front and back axles is missing. As both ends are bolted flanges and the car is not compressed lengthwise, this would not happen as part of the crash; it must be deliberate lightening by the film crew.

Revealing mistake: At the end when we see all the police arrive, there are tyre marks in the sand where they stopped in previous takes. (01:33:15)
Revealing mistake: When the tanker first rams Dom, if you look at the background outside the car it is barely moving. Not even close to the speed we see them traveling at. (00:03:40)
Revealing mistake: When Dom and Letty get out the car at the crash scene, there is a light reflected in the paintwork quite low. When the camera pans out you can see it's not the moon due to its position, and there is no other light source around that could cause the light to be reflected so low on the car. (00:19:15)
Answer: No it doesn't ignore 2 Fast 2 Furious, Brian even references it a couple of times. In that movie, Brian was promised a 'clean slate' if he helped them out which presumably gives him the option to rejoin a law enforcement agency. That he chose not to open a garage with Roman is pretty much redundant, Brian simply got a better offer, and as he stated in Fast & Furious with his conversation with Mia, "I'm a good liar".
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