https://us.motorsport.com/automotive/ne ... e/2275879/
From SFI 38.1
The test sled shall be propelled to produce the racing acceleration pulse (Figures 2A and 2B) at a nominal 68G peak, 63 KPH (39.1 mph) velocity change. For initial design validation, two (2) frontal tests and one (1) 30° right frontal test will be required. The results of both frontal tests and the 30° right frontal test must meet the requirements of paragraph 6.1.1. For periodic revalidation, one (1) frontal test and one (1) 30° right frontal test will be required. The results of the frontal test and the 30° right frontal test must meet the requirements of paragraph 6.1.1.