1957 Ford Thunderbird: The Supercharged F-Code and the Race Program That Ended Around It

The first supercharged Thunderbirds were built for a rulebook, not a showroom. According to John Gunnell, writing in Old Cars Weekly, the first 15 production supercharged cars were reportedly built in January 1957 to homologate the engine for NASCAR competition. They were D-series cars, carrying the 312 four-barrel V-8, fitted with Paxton-McCulloch superchargers, and Gunnell places their serial numbers near 30,000. Behind them stood a racing operation that had already been working on Thunderbirds: Peter DePaolo Engineering in Long Beach, California, had modified the factory-sponsored 1956 cars, and its Gus Davis developed a dual-point distributor.¹

The blown Thunderbird proved its point on the sand before the season's politics caught up with it. At the 1957 Daytona Spring Speed Week trials, Gunnell writes, a modified supercharged Thunderbird with a crankshaft stroked a quarter-inch, lightweight aerodynamic body panels and a strengthened gearbox and rear axle beat the Corvettes and ran the two-way flying mile on the beach at 138.755 mph. Later that year, he adds, the car topped 160 mph at Bonneville. That was a race-prepared machine, not a showroom Thunderbird, and the article does not name its driver. What it showed was what Ford's supercharged 312 could become.¹

The car those racers were based on was having its best year. Old Cars Weekly and the Classic Thunderbird Club International both give 21,380 Thunderbirds for 1957, the most of the three two-seat years, and 53,166 two-seaters for 1955 through 1957. Old Cars Weekly prices the car at $3,383 with the hardtop and $3,438 as a convertible, without stating the basis, and says some 75 percent of 1957s had the porthole hardtop. A three-speed manual was standard and the tires were 7.50 by 14. Most of the 21,380, on those figures, left the factory as comfortable two-seat tourers rather than anything built for the sand.^1,2

Under the hood, the engine chart ran from mild to wild, with ratings that were period advertised gross figures as the sources report them. The C-code 292 two-barrel made 212 hp, and the club says it came only with the manual transmission. The D-code 312 Thunderbird Special four-barrel made 245 hp. The E-code 312 with two four-barrel carburetors is given by Old Cars Weekly as 285 hp in one article and 270 hp with 9.7:1 compression in another, and the club gives it as 270 to 285. At the top sat the F-code, the Paxton-McCulloch supercharged 312, which Old Cars Weekly rates at 300 hp and the club at 300 to 360.^1,2

Gunnell describes the F-code's hardware in detail. It used a Paxton-McCulloch VR57 supercharger on the 312 four-barrel, compression lowered to 8.5:1, and a camshaft with 290 degrees of duration against the stock 256. He gives tuned ratings of 325 to 340 hp, and a factory invoice price of $340 for the option; the club gives the supercharger's cost as $500. The two figures sit on different bases, invoice against an unstated one, and neither can correct the other. Gunnell says the F engines, 196 of them, were built from the spring of 1957.^1,2

How many supercharged Thunderbirds exist is a question both sources answer with a hedge. Gunnell counts the 15 DF cars plus 196 F engines and writes that the "official" total of 211 superchargers in the D and F series "is an approximation." The club gives 208 to 211 F-series cars, 14 of them D-F cars rather than 15. Against 21,380 Thunderbirds, even the higher figure means about one car in a hundred. The engine letter alone does not settle a claim, either: the early DF cars were D-coded cars fitted with superchargers, so a D in the serial does not rule one out.^1,2

The club's counts for the other engines are published as approximations too: about 3,300 C-series cars, about 16,423 D-series and about 1,499 E-series. They add up to roughly 21,430, not 21,380, so they cannot be read as an exact partition, but they show the shape of the year: on the club's figures roughly three Thunderbirds in four had the 245-hp four-barrel 312. Old Cars Weekly offers a different picture of the dual-quad car, saying only 10 percent of 1957s were E-codes. That share and the club's count do not agree, and the share is not a count of its own.^2,1

The racing program the F-code was built for did not last the year. In April 1957, Speed Sport's history records, NASCAR disallowed optional equipment such as fuel injection and superchargers in favor of normal production four-barrel carburetors, partly because Ford and Chevrolet had violated its new "Pure Advertising Law." On June 6, 1957, the Automobile Manufacturers Association voted to halt its members' participation in racing and to emphasize safety in advertising. Ford's John Holman said, "I'm in the process of closing up the shop," and Chevrolet's Chuck Daigh said he was going back to California to look for a job. The supercharged Thunderbird had been homologated in January and had lost its reason for being by summer.^3,1

The Thunderbird itself stayed in production into December. The club dates the last 1957 car to December 13, 1957, and its data-plate guide shows the plates changing in the middle of the run: large plates through mid-April 1957, then smaller plates phased in between April 15 and 19 that dropped destination and scheduled-item codes and added transmission and axle codes. That change is a physical marker that helps place a 1957 car in the early or late part of a season that ran until a few weeks before the new year.²

What followed was a different car. Old Cars Weekly records that production of the four-seat 1958 coupe began on January 13, 1958, weeks after the last two-seater, on a 113-inch wheelbase, and that 37,392 were built that year; Wikipedia, citing Hemmings, gives 37,892, and the difference stands unresolved. The 1957 car was the last two-seat Thunderbird of the era, the best-selling of the three, and the one with a supercharger on the option list. About 211 buyers, by the hedged counts, took that option in a year when the racing it was built for had been shut down.^1,4,2