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At the start of the project, we planned to use a 3.27 or 3.55 rear gear ratio and opted to build this Boss for bountiful torque, which is what we got. At 2,200 rpm, the 347 is already making over 300 lb-ft at the rear wheels and continues to provide a nice, flat curve throughout the rpm range. Horsepower came in at 358, which puts us just over 400 flywheel horsepower while estimating 12 percent drivetrain loss-another project goal achieved. Anderson Ford's Rick Anderson noted that we could make another 20-25 hp by using a Holley SysteMax intake manifold, but that we'd lose 30 lb-ft of torque in the process. It's all about what your car needs, and we wanted the low-end grunt for coming out of the corners at the nearest road course.