It's actually what I'm building his old ECORS rig for. Sounds fun. From my understanding it is an Endurance Race. Each class has a time on the track. Stock is 1hr. Man with the most laps wins. Most don't finish from my understanding. It's a part of Pro Rock Racing Series.
Rules
4. Survival- Survival racing is our own unique brand of Endurance racing. Racers can expect to have all limits stretched, all skills tested, and all weak points in their machines found. There will be at least 5 events, but only 4 total that will count towards the points. 1 drop will be given for the season. Courses will consist of rocks, ledges, tight woods, open straight-away, uphill, downhill, side-hill, steep climbs, water crossings, mud, and any other obstacle we can find to test their limits!
a. Max limit of racers per class is 50
b. Racers will qualify with timing systems to determine start order
c. All races will be lap races or corrected time which will be specified in the driver meeting.
d. All cars must pass tech to be allowed to race by a Pro Rock/Pro UTV official
e. The race lengths will be as follow per class: (may be subject to adjustment)
i. Pro Rock Stock Class- 1hr
ii. Pro Rock Modified- 1hr
iii. Pro Rock Unlimited- 2hrs
iv. Pro UTV Unlimited- 1hr