Who?
Chuck daigh
Chuck daigh
What?
Scarab gp-1
Where?
Monte carlo
When?
Xviii monaco gp (may 29, 1960)
Why?
1 - era
1960 was the last year of the two-and-a-half-liter non-supercharged grand prix formula (which had been in use since 1954), and the drivers' and kits' championships in the issue were won respectively by australian driver jack brabham and cooper car co. Ltd. With the rear- or mid-engined cooper climax as the year before.
Lotus and brm also produced rear-engined cars by the time the year 1960 rolled around. Also even ferrari built any such car, fielding it alongside other front-engined cars to achieve the skill to achieve this configuration for their own cars in 1961. Aston martin continued to operate with its own front-engined car, albeit in an updated form.
This effectively marked the end of the dominance of traditional front-engined grand prix cars, which had reigned since the start of gp racing, minus the notable successes of the rear-engined auto-union in the 1930s.
In an unfortunate coincidence, 1960 also saw the delayed appearance of the american scarab gp team with a front-engined car, which proved totally uncompetitive against the new rear-engined cars, and with which it now had to compete. The scarab was made by a company called reventlow automobiles inc, created by a young american, lance reventlow, to fulfill his desire to produce american racing cars to compete on the international stage.
2 - background
Lance reventlow was the wealthy son of woolworth heiress barbara hutton, who financed her son's auto racing.After he began driving race cars in 1955, he turned to experienced californian warren olson to have a particular prepare them in his eyes. In 1957, at the age of 21, reventlow and concrete friend bruce kessler traveled overseas to race cars, with reventlow unsuccessfully racing maserati 200s and a cooper-climax formula 2 1500cc sohc-powered maserati 200s (prepared by warren olson, who accompanied them). During the trip reventlow and kessler visited all over the world. We offer ferrari, maserati and osca racing cars (at maserati reventlow purchased one of their fiat transporters to wear at all times). They then traveled to the uk where they visited lotus, cooper and brm, followed by a visit to brian lister's workshop in cambridge. Reventlow intended to purchase a lister chassis and put a chevrolet v8 engine on it in order to compete in the world sports car championship in a future seeding season, but was unimpressed with what he saw and decided to set up a factory to build his own sports racing team.
Returning to the united states of america along with olson a few weeks later in 1957, reventlow instructed his human rights activist stan mullin to prepare the legal terms for a personal new company reventlow automobiles inc. (Rai) that would allow him to write off losses as tax deductions for several years while he should be realizing his own dream.
Reventlow began hiring trusted professionals who worked in the midst of auto racing in los angeles (some of whom had functional skills in the aviation industry) to build and produce his automobiles, which he named "scarab," named after the egyptian symbol of immortality or, as reventlow occasionally jokingly said, also the dung beetle.
The firm's first specialist was trusted warren olson, who took the position of general highly qualified manager, who was hired to run the scarab program from start to finish.
Rai is housed in 3 bays of olson's store, which was recently relocated to robertson boulevard west of hollywood in los angeles.
Olson note hired dick troutman and tom barnes to erect scarab. You were skilled craftsmen who literally worked together kurtis-kraft known as indy these days. He then hired chuck daigh, a talented mechanic, to build the chevrolet 283cu in the 'small block' pushrod ohv v8 that reventlow wanted to use. Dey was also to be a race car driver.
3 - sports racing cars
Development of scarab sports cars began in a few weeks in 1957. The chevrolet v8 engine was modified, its dimensions consequently increased to about five.5 liters, and it was equipped with a modified form of hilborn fuel injection. The car used fashionable components of european authorship, and the risk was intended for admission to international road racing. It remained built to incredibly high engineering standards with a de dion rear axle and realized the full experience of the members of the new team. The cars were expected to compete in the world sportscar championship in 1958, however, in september fia unexpectedly announced that from 1958 the currently permitted unlimited engine displacement was to be replaced by a good 3 liter displacement. This ruled out the possibility of the scarab, but reventlow decided to continue development of the chevrolet v8 and avoid the european racing process of considering its possibilities.
The first car, the mki, was finally completed in the late winter of 1958, but it became clear that more space was needed for the developing scarab project, as olson still continued to do race preparation in his workshop. At the very beginning of the 1958 summer season. Rai moved into jim nairn's elaborately equipped workshop at 11930 south jefferson boulevard, culver city, los angeles.
The next two mkii sports cars were based here, as were future grand prix cars.
Next door, at 11928 south jefferson blvd, was traco engineering, run by experienced engine builders jim travers and frank kuhn, then joined by olson to build the chevrolet engine. As the team grew, alternative specialists joined rai, most notably phil remington, who oversaw the construction of huge machine tools and who later played a significant role in the technical specification of the ford gt40).
Reventlow still wanted to compete on the international stage with sports cars, and the only possible american engine option under modern rules was a 3 liter (183cc) offenhauser 4-cylinder racing engine. Consequently, in january 1958. Dai purchased the main one from the list at rai's request, and travers and kuhn were tasked with adapting it for use on gasoline for road racing, in order to assess the extent to which it would fit, at the time chevy v8 engines were being developed and used in racing. But the offenhauser didn't include success; it remained overly heavy, had low power, and didn't yet have enough flexibility. Reventlow realized that if he planned to compete in independent corporate car racing, he would need a special racing engine. The offy engine was tried only once in september 1958 in a different kind of car (chassis 003) only to fail to finish. The v8 scarab sports cars were entered in the sports car club of america (scca) racing series in 1958 and came out on top, beating the best european sports cars taking part in the series, including the maserati 450s v8 and the ferrari 412mi v12. This success further boosted reventlow's confidence in the abilities of his american division that decided to build a car to take part in the grand prix to take part in the final two years of the two-and-a-half-liter formula 1. After winning the race at nassau in december 1958, reventlow announced that he would take the race-winning vehicle and convert it for street use, and put the other two scarabs up for purchase, with the proceeds going to fund his project at the nassau race in december 1958. The car would have to be completely american in structure and composition, all of which was the first challenge, as there was almost no experience in designing and building formula one grand prix cars in the states at the time.
After interviewing only a handful of candidates, olson hired marshall whitfield, a young aeronautical engineer working for the douglas aircraft company, to design the chassis and suspension. The car had a traditional concept - space frame, front engine/rear wheel drive with all-round independent suspension. The engine had to be mounted very low, with the crankshaft on the left, so the driveshaft and gearbox remained close to the driver, ensuring a low seating position.
There was another problem for the rai, as earlier in the year the basic two grand prix races had been won by rear-engined cooper-climax cars, which meant a radical change in race car design. Reventlow himself raced rear-engined cars: the sporty cooper t39 "bobtail" in 1956 and the f2 cooper-climax fwb t43 mkii in 1957 and 1958. Rai considered installing a rear-engined layout but preferred the apparent simplicity of a front-engined assembly and reventlow later claimed that, based on the set, he was hired to see the writing on the wall.
In harmony with the principle of using american components, the gearbox was a rai case with four-speed chevrolet corvette gears and an additional case containing the starter gear and analogue, which was fashioned by mechanic "sonny" balken, who had worked previously for olson and afterward for jim hall. At first, reventlow did not permit the use of british disc brakes, and many hours were spent acquiring drum brakes with aircraft-type expansion bladders bringing the pads to life at the front and a water-cooled center disc brake on one of the half-shafts at the rear. As a result, girling disc brakes had to be installed on many of the four wheels.
The shape of the body of the car was determined in the wake of tests of the tablet in the wind tunnel of the cornell aeronautical laboratory, and it was made by an experienced miner emil deidt from aluminum sheet with a thickness of 0.051 inch. The final result had smooth clean lines, reminiscent of the reduced roadster indy.
Reventlow hoped that such a vehicle gp will not mind participating in the race monaco gp in the late spring of 1959. It took only six months to prepare and build the successful sports cars, and everything is affordable, made rai underestimate the time that might be needed to create a more sophisticated gp car. The main advantage was that they were now developing a racing engine from scratch, rather than modifying a production engine.
5 - grand prix engine
Despite the failure of the reduced 4-cylinder offenhauser engine used in the pe cars, reventlow was of the opinion that a directionally organized engine based on a similar design was required. He asked olson to contact the most professional racing engine designer in the united states at the time, leo goossen, chief design engineer at meyer & drake engineering (the manufacturer of the offenhauser), and have him design the engine for the grand prix. Travers and kuhn of traco were to work with goossen to design the engine, and jim nairn was to do most of the machining, as meyer & drake was heavily involved in preparing engines for indycars.
5.1 - engine concept
The scarab gp engine was a bespoke design, not based on the offenhauser 220 "four", although it did incorporate some similar design concepts due to the same designer. It also had to be adapted to the 1.5 and 3-liter engines.
The engine was a water-cooled inline 4-cylinder engine with two valves per cylinder and dohc desmodromic valve train. The original cylinder bore and stroke was 95.2 x 85.2 mm (3.75 x 3.375 in.) With an operating displacement of 2,426 cc, but by the time the scarab began racing, the bore and stroke had been slightly increased to 95.25 x 85.725 mm (3.75 x 3.375 in.) With an operating displacement of 2,443 cc. Four cylinders were chosen for reasons of simplicity and the possibility of good mid-range torque. The recent successes of the british gp 4-cylinder engines had not gone unnoticed.
The engine was rigidly mounted in a recumbent position at an angle of 11° to the horizontal with the crankshaft on the left. This allowed for a very low hood line due to the wide body shape.
But the engine became the team's next major challenge due to the decision to use desmodromic valve control. This system utilized an opening and closing cam for each valve, providing completely mechanical control of valve movement without the use of valve springs. It allowed more radical variation in valve opening and closing periods and protected against problems with valves operating at higher rpm. However, it required very precise manufacturing tolerances and the ability to fine-tune the opening and closing phases of the cams to ensure a smooth transition. At that time, only daimler benz with all its engineering resources had perfected this system, which was used in their victorious mercedes-benz m196 and m196.I racing engines in 1954-55 (osca also developed a desmodromic system in 1957)
Goossen had planned a relatively simple inline 4-cylinder racing engine, but reventlow, travers and kuhn were fascinated by the concept of desmodromic valve control. This was made possible by the experience the traco founders had gained in 1957 when ford was considering a racing engine for indy. Ford asked pete depaolo, who ran its sports car racing team, to explore the possibility of building an engine for indy, and he enlisted travers and kuhn to work on the project. As it turned out, ford had received a mercedes-benz 300slr sports racing car (powered by the m196.I engine) in exchange for allowing daimler-benz engineers to study production methods, and it was decided that travers and kuhn could take the mercedes to evaluate its advanced performance. The mercedes was in the henry ford museum, and the museum staff allowed travers and kuhn to take it only on the condition that they would restore the car to running condition after they finished studying it.
Travers and kuhn disassembled the mercedes benz 300slr and took scarab wins casino review its parts to the engineering department. They made detailed drawings of all the parts, particularly the desmodromic valve train, and then provided ford with their findings. The car was then returned to the museum in running condition as promised. Before this information could be used, however, in june 1957 all automakers agreed to a ban on direct factory participation in auto racing, and ford discontinued the project in accordance with this decision.
However, travers and kuhn had acquired copies of the drawings and engineering data from their research and believed strongly in the advantages of the desmodromic valve train used in the mercedes. Reventlow and company were equally enthusiastic about this advanced feature, so they pressured goossen to incorporate it into the scarab gp engine design, even though he was against it.
5.2 - detailed scarab engine design
Note: during the design of the scarab gp car in america, it was customary to express dimensions in inches and fractions of an inch. In this article, i have converted the dimensions to the more familiar metric measures with the decimal equivalent in inches.
5.2.1 - crankcase/cylinder block
The engine had a combined crankcase and cylinder block cast in aluminum alloy, with a closed top area designed to accommodate pressurized wet cylinder liners. The crankcase extended down to the level of the upper main bearing caps, each secured by two 12.7 mm (0.5 in.) Diameter studs screwed 50.8 mm (2 in.) Into the crankcase. The main bearing caps were secured with aircraft-grade "nyloc" high-temperature nuts. There were five crankshaft main bearings. The three intermediate bearing caps were also bolted with the caps through the crankcase walls, and the two end bearing caps rested transversely on the crankcase ends.
Because of the severe rightward tilt of the engine, the bottom of the crankcase below the crankshaft had eight heavily ribbed rectangular holes along its entire length to drain oil into a molded manifold pan, which was mounted above them and pressed against a round neoprene seal mounted in a slot milled in the crankcase face. The open bottom of the crankcase (facing the left side of the engine compartment) was covered by a ribbed alloy casting that was bolted on the outside and rested against the top surfaces of the main bearing caps, providing nearly 360° of support. (It is true that phil remington later claimed that the engine crankcase sagged in the quest for more power.)
The engine had no gaskets, and all mating surfaces were machined. Each oil and water passage in the block head was surrounded by a recessed neoprene o-ring.
The wet cylinder liners were made of steel and had a top flange that was mounted in the block. Around this flange, a circular groove was milled into the block face to accommodate hollow gas-filled copper o-rings, which expanded at engine temperature and provided a fireproof seal between the block and cylinder head. Two neoprene o-rings were inserted into the bottom of the cylinder liners to retain coolant and a similar ring at the top of the liner. By design, the outer surface of the liners was smooth, but the racing version of the engine used liners with a small ribbed surface in contact with the cooling water.
The front surface of the crankcase/cylinder block extended laterally to provide rear mounts for the camshaft, accessory gears, and magneto, and the rear surface extended to form half of the clutch crankcase, on which a self-starter mount was provided. Olson misinterpreted fia rules, and they included this feature, as well as the reverse gear, which were only required for the upcoming new 1961 gp formula.
A large rectangular breather was attached to the top surface of the crankcase, at the back near its bottom edge. It was covered by a cap at the top and rose quite a bit above the engine. On the breather side was a flexible hose leading to the oil tank.
5.2.2 - cylinder head and valves
The engine had a removable cylinder head, cast from aluminum alloy, which was held on 10 studs screwed into the block. There were two stainless steel valves per cylinder, symmetrically arranged at a valve engagement angle of 84° with inset seats in hemispherical combustion chambers. On either side of the valves on the longitudinal axis of the engine were two disguised spark plug diverters. The intake valves had a head diameter of 48 mm (1.89 in) and the exhaust valves had a head diameter of 46.5 mm (1.83 in), both with 9.53 mm (0.375 in) diameter stems. Short valve guides were inserted into the head, which were separated for ease of assembly as the ends of the valve stems were larger in diameter with two machined slots to accommodate the valve return fork. Larger diameter pushrod guides were inserted on top of the guides, which did not engage the splines on the ends of the valve stems.
The round intake ports were 44.45 mm (1.75 in.) In diameter, had a very slight elevation angle of 7° to the plane of the cylinder head, and were tilted in plan view 15° to the transverse axis of the engine to promote tangential swirl in the combustion chambers. The front two ports were tilted backward and the rear two ports were tilted forward, resulting in closer spacing of the inner two ports. The exhaust passages in the head went from a round shape at the valve throat to a rectangular shape (with rounded corners) at the port end, where they were 35.52 mm (1.4 in) high and 57.4 mm (2.26 in) wide. (This shape replicates that used on the offenhauser 220 engine, but there it served two exhaust valves per cylinder.) The exhaust ports exited parallel to the end of the cylinder head.
The velocity of the gases in the intake ports was quite high at the planned peak power of 7,500 rpm - 97.5 m/s (320 ft/s), which provided good ramming inertia.
The two upper camshafts were driven by a drive of eight spur gears located forward of the crankshaft (four forward of the cylinder head), which rotated on roller bearings. The camshafts