The word billet has been teased out of proportion in the last few years; everything is billet now and the previously innocuous material terminology is now synonymous with strength and quality. Billet parts imply that a series of machining operations led to the final product — there has been no mechanical forming techniques involved such as casting or forging, to establish a rough shape before a CNC mill makes the final few cleanup passes.
Billet parts’ strength is often attributed to the quality control of the base material. Casting can introduce inclusions (contaminants) in the form of non-alloying debris that weaken the final block. Forgings can suffer from lean areas where there was insufficient material to fill the die, and often have imbued stresses unless heat-treated properly.
Manufacturing from a billet aluminum block is arguably the cleanest slate in that it is as neutral and predictable as possible in its properties. CFE Racing is known for their variety of billet engine blocks both big-block and small-block for the “big three.” Among their stout offerings are even specialty designs featuring altered bore-spacing to cram more inches in an already big package.
The 5.300-inch bore spacing big-block Chevy billet block we get a closer look at here was machined from 6061-T6 aluminum, and features a 5.010-inch bore, 1.095-inch lifter bores, hard-coated 4-bolt splayed aluminum mains and a dry deck for extra solid strength. Intended for Pro Mod racers, this billet block makes a solid foundation for extreme power outputs and durability. For more information check out CFE Racing.