Factual error: The Russian submarine is propped up on steel supports with its propeller well out of the water, so there is no way it could have been launched so quickly. Filling a dry dock and launching usually takes several hours.
Plot hole: Dom arrives in New York at the same time as Hobbs and his team. Dom meets up with Shaw's mum and then proceeds to steal the nuclear codes. Meanwhile at the same time, Hobbs and the team arrive at their secret hideout and start preparing the cars. The time frame isn't the same - Hobbs and co. simply haven't got the time.
Continuity mistake: Near the end, the Russian chase vehicle fires a grenade at Hobbs' vehicle. The tube on the top far right is used and can be seen open. When that same vehicle goes for the second shot at Hobbs, the tube that was used before is unused now. When Dom hits the vehicle shortly after that there is a very close shot that shows that despite having just fired another round the array of tubes is again unused. (01:51:05 - 01:51:55)