If you want your Ranchero to still look stock under the hood, find a set of the 271 hp 289 heads with the matching intake, 270 duration cam, and a set of tri-y headers. Top it off with the "Cobra" valve covers and air cleaner, a 600 Holley vaccuum secondary carb, and upgrade to an electronic distributor.

If stock looking under the hood is not a consideration, then go with Tech and Mike, swap in a 351 W. If you want way big torque, get the 408 ci strker kit and aluminum heads with a good cam.