427SO and NASCAR

[Joe Rutledge]

Ford race 427's blocks were all specially cast with an even higher nickel content than production blocks, a fact that fairly well know in the drag race world long ago. Only the factory supported racers in the know received the special pieces. The standard 427 block is excellent, just wouldn't hold up in blower use (such as a fuel 427 cammer). Lack of special race blocks was the reason the last successful cammer funny car (Tommy Grove) went Chrysler hemi in the early/mid seventies. As said before, later on the true "race" engines had the "NASCAR" crank and rods with wider journals/heavier rods. These were the true "LeMans" pieces, being designed for both LeMans endurance racing and NASCAR. Somehow the production pieces (with capscrew rods) were later dubbed "LeMans", probably to differentiate them from the original "nut and bolt" rods of the early 427's (and 390's/428's). The capscrew rod was a strong but finicky rod its day, with the capscrews being the major reliability culprit. Standard "nut and bolt" rods, while not good enough for NASCAR and endurance racing, were plenty strong, and preferred by drag racers because they were lighter than the capscrew variety, and didn't come apart because one of the factory capscrews failed. Since the "nut and bolt" rods seldom had capscrew type problems, they were often more reliable. In the 60's Ford used both medium riser heads, and later the tunnel port heads in NASCAR. You can be assured that the pieces being raced by the major teams were subtly different than production pieces normally sold in that every trick Holman Moody had discovered made it into the castings used for racing.