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PORSCHE TYPE 360 CISITALIA GP CAR—ANALYZED BY POM AND OTHERS PART 2

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YESTERDAY, LAURENCE POMEROY MADE a tantalizing comment about the Porsche Type 360 Cisitalia GP car—an apparent necessity of its four-wheel drive. This, recall, in 1947. Today in Part 2 we continue with analyses gleaned from Pom’s The Grand Prix Car Vol. 2.

The Type 360’s general layout. Compactness of the engine and gearbox is noteworthy, as is the deep headrest housing the down-draft carbs. This and following images from The Grand Prix Car.

The Type 360’s Transmission, per Pom: “Power is transmitted through a 7 1/2-in. diameter multi-plate clutch to a five-speed gearbox mounted surprisingly between the engine and bevel box. The gearcase is split vertically on the centre line, a necessity in view of the novel gear engagement system employed.”

He continued, “A pair of constant-mesh wheels takes the drive from the clutch shaft down to a shaft lying in a lower plane. Surrounding this lower shaft are five gear wheels in constant mesh with corresponding gears fixed to the upper shaft which drives the bevel pinion. The lower gears are each separately mounted on a ball bearing with the lower drive shaft running freely inside them, and by moving a sleeve horizontally in relation to the lower train of gears successive ratios can be picked up by external serrations on the sleeve engaging with internal splines on the gears.” 

The Type 360’s sequential gearbox. Image from Stuttcars.

“This,” Pom noted, “gives an exceptionally compact layout but, in effect, a quadrant gear change in which a change from fifth to second speed demands the momentary engagement of the fourth and third ratio.”

Such a design is a “progressive gearbox,” common only in motorcycles back then (and modern race cars these days). 

Four-wheel drive was driver-engaged.

Four-Wheel Drive. Pom described, “A spur type gear engaging with the lower gear shaft transmits power to a two-piece open propeller shaft (running 7 1/2 in. below the hub centres) forward to a train of three gears and a bevel box at the front of the car. This drive could be brought in at will by means of dog clutch and a lever placed below the steering column….”

Lever beneath steering column engaged four-wheel-drive. No starter motor was included; thus the fitting of a crank handle.

Suspension. At the front, “a conventional Porsche layout with trailing arms on each side” carried the wheels on ball joints, connected to transverse torsion bars. The Type 360’s rear wheels were “located longitudinally by fabricated radius arms 31 in. between centres splayed out at 9 degrees. The hubs were connected to the frame by equal length (8.7 in.) arms on each side, a third arm used for the hydraulic damper.”

Bodywork. Pom observed, “As the whole of the tail of the Cisitalia is occupied by the engine and transmission aggregate, side-tanks were a virtual necessity more especially as the squab of the driver’s seat is slightly nearer the rear axle than the front. A single filler is provided for the tanks just ahead of the windscreen and the tanks themselves are designed in some degree to act as fairings behind the front wheels.” 

Estimated Performance. Stuttcars offers “A theoretical calculation was made which helped to decide for the 4-wheel-drive.” Among these was “a standing-start 1 kilometre with road friction of 1.0: 181.1 km/h [110.0 mph] for the 650-kg [1433-lb] rear-wheel-drive configuration compared to 191.0 km/h [115.8 mph] for the 720-kg [1588-lb.] 4-wheel-drive choice.” The base data were 300 PS/221 kW (“guaranteed minimum power”), drag coefficient Cw 0.288 (maximum). 

Also offered by Stuttcars was a theoretical top speed of 209 mph/337 km/h or, with an optional gear set 228 mph/367 km/h.

High Hopes, But.… “While Dusio’s dream plan,” Stuttcars recounts, “saw many Cisitalias already running at the 1948 Grand Prix events, he didn’t have the money to fulfill his dream. The first car was put together by the end of 1948, but it was not ready to race.”

Gone Bust. “In January 1949,” Stuttcars reports, “the Cisitalia company was basically bankrupt because of the Grand Prix project, wages were unpaid. Carlo Abarth got his pay in a few Cisitalia road and racing cars and left Cisitalia to establish his own ‘Abarth’ company in March.”

An Argentine Rescue? Stuttcars says, “With financial hard times in Europe, Dusio found new supporters in Argentina and already in March 1949 a company called Autoar (Automotores Argentinos) was founded.”

“So,” Stuttcars continues, “in the end of 1950 the car was taken or sold to Argentina, depends on how you look at it. Dusio got 50,000,000 Italian lira for selling the car to the Autoar company he now worked for. A source says in Argentina the engine power was measured at 365 hp at 8000 rpm and 385 at 10,600 rpm, but then the pistons were damaged.”

The car hung around Argentina, with famed drivers including an elderly Tazio Nuvolari and youthful Paul Frère photographed with it.

The Type 360 and Paul Frère, Argentina.  

Peron’s National Pride? “Then, on June 18, 1953,” Stuttcars reports, “an event was set up on the Buenos Aires to Ezeiza highway to set a new South American speed record on 1 kilometre. The previous record 109 mph/176 km/h was from 1934, so 19 years later it just took to start up the engine to beat it…. A new record was set, but Bucci could finally only do a lousy 145 mph/233 km/h.”

Our Takeaway. Should we lament the lack of Piero Dusio’s development cash? Or celebrate his 50 million lira from the Argentine? Or just enjoy Pom’s enthusiasm for technicalities of the Type 360 Cisitalia GP? Or all three. ds

© Dennis Simanaitis, SimanaitisSays.com, 2024


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