Burnout CRASH!

For this achievement you need to get to the end of a pile up event without any cars getting away and without any cars blowing up (so you cant use your crashbreaker). The hardest part is at the very start as its tricky for cars not to pass you without the use of your crashbreaker. It may take a few attempts but you need to try and crash into the first car so it covers a lane while keeping yours in the other one. Now you just need to sit there and wait for the rest of the cars to pile up on the existing ones. The first time i tried this some cars blew up anyway but i was able to get this easily on my second attempt. I think the more times a car is hit the more likely it will set on fire and blow up but as there is no easy way to control the cars while going for this it may take some trial and error.
I also combined this with the "Set 'Em Up, Knock 'Em Down" achievement by using a crashbreaker after this achievement popped as all the cars that had piled up around me blew up simultaneously and flew into buildings etc all combined with the 5x multiplier. You can also use a second crashbreaker if you still dont have enough points
Edit: Easiest to do on the first pile up event in windrush