Intimidator 305 at Kings Dominion. I rode it the 2nd day that it was open and blacked out on the first turn. I came to like halfway throughout the ride and was like da fuq just happened. Now they put some safety shit on so its not as fun anymore.
Quote about modifications to it:
"Some riders experienced problems due to the G-forces inherent in the ride's original design. Riders reported greying or blacking out after the first drop. Kings Dominion temporarily installed trim brakes on the first drop in order to reduce the speed while a long-term solution could be devised. The brakes were adjusted and positioned by late May 2010."