315-376-8013 I would give that number a call. It is D&D Racing, they deal with Cats and every cat guy I know runs straight D&D stuff. I don't know if they have anything for the ZL 800 EFI yet. Give them a rign they can tell you. I have heard about it being difficult just to open the EFI box to change the chip. If this is true I would be very upset with Cat for not allowing someone to modify a sled. A chip would probably help out of the hole or a torque pipe. Twins will help up top but not as much down bottom.