Continuity mistake: Brian's number plate gets shot off at the end in the desert. However it reappears in a couple of shots in the tunnels. (01:28:00)
Continuity mistake: When the girl is asking for Dom's number at the end of the first race her hair is in her jacket in some shots and not in others. (00:43:00)
Continuity mistake: Dom lets go of David Park and Brian rushes forward to grab him. Dom vanishes instantly, for Brian to get past him. (00:29:50)
Continuity mistake: When Mia hugs Dom in the garage, her hands keep changing position and grasp on Dom's shoulder. (00:16:50)
Continuity mistake: When the truck driver shoots at Dom at the start, we see his window smash in on him. Camera changes and it smashes again, but this time it smashes out, on to the road. (00:03:50)
Continuity mistake: When Dom crushes Phoenix between the Camaro and Impreza, the hood of the Camaro is badly damaged and denting up. In every shot afterwards, the Camaro is just fine. (01:35:50)
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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