Ford Lightning & Harley truck 10 1/2-inch multi-disc torque converter. Designed by Precision Industries for WOT lock up. The standard performance gain reported is 2 tenths on 60 foot times and up to 3/4 of a second on overall elapsed times in the 1/4 mile. The front cover of the converter is machined out of billet steel to ensure durability and to allow us to significantly increase the clutch surface area.The 10 1/2-inch Stallion torque converter is a favorite of Lightning/Harley owners looking enhance the performance of their trucks with out sacrificing drivability. The "best of both worlds" as it is referred to, becomes a reality. The 10 1/2-inch series is capable of withstanding horsepower ranges up to 1600. The average build time is 3 to 4 working days. The stall speed on the 10 1/2-inch Stallion is available from 2400-5800 rpm's depending on the application.