At the annual "hoods off" festival this summer at the Revs Institute in Naples, Florida, visitors were treated not only to a spectacular show of priceless engines, but also to a rare peek inside the Institute's fabled workshop. In the photo above, the car in the foreground is a 1958 Scarab* Mk. 1. A 1965 Ferrari 250LM* is tucked under the stairway, while to the right we can spot a '64 Alfa Romeo GTZ*, which became known as the TZ1 after Alfa got around to making a TZ2. The other blue car is a Ballot racer from the era immediately after World War 1. Like the Peugeot in our previous post, the Ballot used a twin-cam engine designed by Ernest Henry. For the Ballot design, Henry doubled the cylinders for an inline 8, and concealed the valve springs which had been exposed on the Peugeot. The 4.8 liter Ballot racers finished 4th and 11th at Indy in 1919, and took 2nd, 5th and 7th the next year. Like the successful 3 liter Ballot GP cars, they've been somewhat forgotten because Edouard Ballot left the car business in 1932. Henry's Peugeot and Ballot engine designs, however, have been credited by historians for inspiring Harry Miller's engines...
The Institute has what is likely the most famous OSCA* ever, the 1954 MT4 / 1500 that Stirling Moss and Bill Lloyd drove to an outright victory in that year's Sebring 12 Hour endurance race. The 1491 cc inline four features a cast iron block, aluminum head with twin chain-driven overhead cams, and two spark plugs per cylinder. This race made Moss, who drove most of the distance, famous in America. It also generated demand for the expensive OSCA sports racers, which cost around $10,000. In taking the overall victory as well as winning its class, the Moss OSCA beat a much more powerful 3.3 liter Lancia as well as a factory Special Test Austin Healey with 2.6 liter engine...
Bore and stroke were equal at 78 mm. Later on, OSCA's founding Maserati brothers experimented with desmodromic valves (mechanically opened and closed) and shared their 1500 and 1600 engine designs with Fiat for some special Fiat 2 seaters...
The year after Moss and the OSCA won Sebring, Briggs Cunningham* and his team of engineers and mechanics produced their last new sports racer aimed at finally attaining victory in the Le Mans 24 Hours. Previous attempts with the Chrysler-powered C2, C4R and C5R had resulted in two 3rd place finishes, as well as a number of top-ten placements. So Cunningham decided to switch to a real racing engine, the Offenhauser inline four with twin overhead cams and four valves per cylinder.
The Offenhauser had been designed to deliver its power on the methanol fuel used at the Indy 500 and other oval-track races. In 3 liter form as used in the new C6R, the Offy produced 220 hp with Hillborn fuel injection and 270 hp with Weber carburetors and the pump gas specified for Le Mans...
But the gasoline-powered engine ran at higher temperatures than the methanol-fueled version, and the Cunningham team was never able to get the running temperature down to a satisfactory level, despite frequent consulting with Offy engineer Leo Goosen.
In the ill-fated, accident-plagued running of the 1955 Le Mans, John Fitch and Phil Walters went 202 laps in the C6R before the high temperatures cost them a piston. The C6R engine, however, shown in the 3 photos above, remains a work of art… Another twin-cam inline four from the same era had its roots in a humble fire pump engine. The 2.5 liter Coventry Climax engine was used by Cooper as well as Lotus teams, and powered Cooper and driver Jack Brabham in back-to-back World Championship wins in 1959 and '60.
The original FW (featherweight) fire pump engine was just over a liter in size, and with its aluminum block and head with single overhead cam, caught on with racers in the 1,100 cc class in FWA (featherweight automobile) form. Eventually it was produced in 1.5 liter and 1.9 liter forms, now with twin cams, and the definitive FPF 2.5 liter produced just under 100 hp per liter...
The key to the Cooper's success in the hands of Stirling Moss and Jack Brabham was not the engine however…it was its placement in the chassis, behind the driver and ahead of the transaxle. Along with low weight and frontal area, optimal weight distribution and predictable handling allowed the Cooper drivers to defeat the front engined V6 offerings from Ferrari.
The Italians derided the simple, austerely finished Cooper as the product of a bunch of blacksmiths, but those two Championships caused an revolution. All competitive Formula One cars, including Phil Hill's Championship-winning Ferrari, were mid-engined by 1961.
A few years before the mid-engined revolution, engineering of production engines began to produce designs that were competitive with designs that were focused only on racing. First the Jaguar XK twin-cam six, designed for a big sedan, won Le Mans in 1951 & '53 (later victories were '55 thru '57). In 1954 Alfa Romeo introduced its twin cam Giulietta, with aluminum block and head, twin cams and eventually up to 129 hp in 1,300 cc Veloce form. Specialists like Conrero* offered twin-plug heads as well as 1,500 cc versions, and the ageless engine went on to power the Zagato-bodied GTZ lightweight at left below, sometimes in twin-plug form...
Abarth was beginning to achieve good results with highly-tuned versions of the production Fiat 600. The 1000 TC-R below managed 112 hp from a 982cc pushrod four, with special aluminum heads and hemispherical combustion chambers. The line between production engines and racing engines was beginning to blur...
By 1962, however, Carlo Abarth introduced his own engine for GT competition in the Abarth Simca, at first in 1,300 cc and later as a 1,600 cc. The culmination was the 2 Mila, a 2,000 cc twin-cam four with twin-spark head design and lightweight block by engineer Mario Colucci. The car used a shortened Simca 1000 sedan chassis, but the engines and transmissions (in 4, 5 and 6 speed versions were entirely of Abarth manufacture..
The 2 Mila's success in endurance racing was limited by the fragility of the transmissions, which had to cope with between 192 and 202 hp. The Abarth Simcas had real success in hillclimbs, however, beating Alfa and Porsche to win the European Mountain Championship in 1964.
Ford Motor Company, like Cunningham, decided to challenge the Europeans, especially Ferrari, at Le Mans, launched their GT40* in 1964. The car was originally powered by the 4-cam, aluminum-block 255 Ford Indy V8 engine (loosely based on the production 260) that would win at Indy in '65. Below is a rare photo of Ford's full-race, 425 hp Indy engine mounted in an early GT40.
Concerns about the reliability of an engine designed to run a 500 mile race now being asked to run over 2,800 miles led Ford to adapt their production 289 for use in the GT40...
While Ford's first victory at Le Mans, a 1-2-3 finish in 1966, was with the 7-liter GT40 Mk. II, and the '67 win was with the 7-liter Mk. IV, the 1968 and 1969 wins were perhaps the sweetest...
…because Ford claimed back-to-back wins with their 4.9 liter engine and ZF transaxle in the Mk. I, which was at the end a 5-year old design. Five years is a long time in race car design, and the GT40, like the D-Type Jaguar in the Fifties, had become the Old Faithful of endurance road racing cars. The line between racing engines and production engines continued to blur...
In the early 1990s, designer Gordon Murray selected the 60 degree BMW V12 as the basis for a new supercar. By the time the car was unveiled in 1992, McLaren had won the Indianapolis 500 three times and six Formula 1 Championships. Maybe this colored the decision to make the new car a practical and tractable road car, but one which could compete in road races...in a way, a throwback to the "dual-purpose" sports cars of the Fifties and early Sixties. The BMW engine as it appeared in the F1 was based on the SOHC production V12, but was a 4-cam design with 4 valves per cylinder, and developed over 620 hp from 6.1 liters. The 3-seat, center-steering F1 weighed 2,244 pounds, around the same as a Mazda Miata. Top speed was 240 mph. A McLaren F1 won the Le Mans 24 Hours in 1995.
Footnote: *Asterisk indicates there is an essay with photos on the car indicated. Searching the Archives will lead to essays on the Abarth, Alfa Zagato, Ferrari 250LM, Scarab, OSCA, Cunningham, and Conrero Alfa, as well as Ford's GT40.
Photo credits: All photos were taken and supplied by Paul Anderson, with the following exceptions:
Ballot engine: The Miller / Offenhauser Historical Society, milleroffy.com
Abarth 2000 engine from Abarth Simca: The Revs Institute
Ford 255 four-cam engine in early GT40: Ford Motor Company, reproduced on gt40.net.
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