This is the 4L80E of choice for most applications up to 850 horsepower. This trans features all the components and upgrades of the SS model with the addition of a 300m billet steel input shaft, high strength billet clutch hub, extra capacity high energy clutch packs and bands as well as additional shift and durability modifications to handle huge horsepower and torque. The SX transmission includes our 2500 stall torque converter, but can be optioned with stall speeds up to 4500rpm, and also available with upgrades for extreme applications beyond 1000HP, ask your salesperson for details.