Revealing mistake: Dom pours petrol over the money to make a point to Reyes. When he does, he pours a small bit on the top and chucks the can away. When he throws the lighter, the entire mound goes up instantly. Even areas with no petrol, and nowhere near the lighter. (00:47:05)
Suggested correction: Petrol is a liquid and as such it will run down from the top as well as the splashing of him pouring it. It will all go up instantly same as if you petrol to start a bonfire.