Xcelerator is a roller coaster in The Boardwalk at Knott's Berry Farm. While it's not the best, it is also recommended. The minimum height to ride is 52 inches.
An Intamin accelerator coaster, themed to be flame-emblazoned '57 Chevys, taking you from zero to 82 mph in 2.3 seconds. You launch up 205 feet in the air, then drop straight back down. Adds 2.2 gs during the acceleration.