TD Motion Conversion Kits offer 427W - 538 HP Crate Engine for Classic Mustang or Restomod. A perfect fit engine with everything included. Our Most aggressive Small Block Ford. Classic Muscle Car Idle, ample Vacuum, Strong Torque + power range. This Engine is a Direct replacement in most 65-73 Mustang for your old 289, 302, 351W. Nice upgrades and performance improvements. Brand New Heavy Duty 4 Bolt Main Dart Block, not a “Performance Equivalent or Chinese aftermarket block. All Forged internals, 4 bolt main Block, Roller Valvetrain. Cylinder Heads Flow exceptionally better than the old Iron Heads. Classic Thump Idle sound. Will Replace most early 260, 289, 302, 351w, and later model Small Block Ford Engines. Pump Gas Friendly – 91 octane and up.