HOT ROD SLED SHOP has performance ECU mapping for the Ski-doo 850 ETEC. We have a reflash for your sled that increases acceleration. Maps are available for short drag, lake race and performance trail. Gains of 6 -8 hp are achievable. Proper fueling is required for some mapping. We have modified parameters such as fueling, timing, speed, rpm, AFR targets, exhaust valve timing and more. You can send us your ECU to be flashed or bring the sled to our shop for quick turnaround. Call for an appointment or questions!