Suzuki DF9.9BT EFI L. Outboard Motor. Suzuki’s High-Thrust 9.9 horsepower 4-stroke was specially designed for slammin’ salmon and whackin’ walleye. The new Batteryless EFI powerhead with an integrated power tilt system makes raising and lowering Suzuki’s DF9.9TH High Thrust a breeze. With plenty of torque, a high-thrust propeller and a 2.08:1 gear ratio deliver efficient and reliable low-speed trolling for a range of heavy fishing boats.