When Size Does Matter

How to decode the evolution of Ford’s 427, 428, and 429 big block muscle

by Colin Comer

Ford 427, 428, 429. What do these similar numbers tell us about very different engines?

To the uninitiated, Ford’s big inch performance motors all seem basically the same, with slightly different displacements. Nothing could be further from the truth. That last digit can make a really big difference in both performance and value of Blue Oval muscle.

Rather than try to spell out every technical aspect of these engines, let’s look at them as they relate to cars that interest us—namely, Shelby and Mustang cars. The 427 and 428 engines are both from the “FE” family, in production from 1958–76, with engines that ranged from 332 cubic inches to 428. The first performance-era FE was the HiPo 390, followed by the 406, which was developed for racing and based on this 390, but with a thicker walled casting block, cross-bolted main bearing caps for high-rpm...