most dirt cars dont run alternators, and its the only place i know of a good electric fan properly set up and wired wont work! it cause of the sustained high rpms over time! go check out a good super street class or one of the chevy crate engine class's thay all have biggest double pass aluminum radiators that fit, 1 to 1 pulleys and a fixed 4 blade fan! anything less and by end of 30 to 50 laps will be pulling in pits puking coolant!! if thay running that E85 and run up front in clean air then some will cut 2 blades off but every piece of the cooling system will be high dollar CV products and thay still 220 to 240 degrees at end of 30 laps!