The human body can suffer blackouts when g-forces reach 4-6. Check out what a F1 driver endures.



http://www.youtube.com/watch?v=a4Fmy...layer_embedded

 

The body only suffers a blackout if it's a vertical G. Forwards, backwards, sideways do all put a tremendous strain on the body, but at least you won't blackout. Crazy how much G they have stopping, I didn't realize they drove quite like that (I was hoping they did, but just didn't know for sure). That will leave some eyeball on your visor for sure.

 

Sebastian Vettel is the fastest of everyone bahhhh. Yeah they go up to 5G lateral. They have to all be 100% fit when they race.