Search Home Contact Us Blogs Member Login Renew Join PCA
Follow us on Facebook and Twitter912 & 912E Register Home > 912+912E History > 902 Prototype and Research Cars
Part 2: Type 902 Prototypes and Versuchwagens [Research Cars]

The 902 Decision

As Porsche refined the design of the six-cylinder Type 901 [later 911], it became clear that production costs would drive 901 retail prices significantly higher that the standard Type 356.  To assure sufficient sales, in 1963 Porsche executives decided to also introduce a four-cylinder version, to be known as the Type 902 [later 912].  With Autumn 1964 911 introductory sales figures unstable, to the rescue came the 912 option in April 1965.  Porsche brought 912 pricing close to the 356 by installing a four-cylinder engine, plus making optional some features standard on the 901.

The 902 Engine

Porsche's Carrera 2 four-cylinder engine, though 2.0 liters and 130+ HP, was too complex and costly for the 902.  Therefore Porsche first considered designing a completely new four-cylinder engine for the 902, utilizing components from the new 901 six-cylinder.  Paul Hensler (later Porsche Chief Engineer and leader of development of engines and drives) joined the engine construction department on April 1, 1963 and took the project as his first street car engine design.  Because the new 901 engine was 2.0 liters, using those components would result in a 1.3 liter four-cylinder version.  Even a 1.5 liter version would only have produce about 100 HP; therefore Porsche shelved this design concept.

Another option explored by Claus von Rucker in mid-1963 was to modernize the 356 Type 616 engine by increasing displacement to 1.8 liters, adding Kugelfischer fuel injection, and modifying both valve and cooling systems.  By the influence of the Sales Department, this project was shelved when cost calculations by Hanz Mezger did not support further development. 

1965 912 Type 616/36 engine with Mann & Hummel air cleaners.  Image © Porsche AGUltimately a new, refined version of the 356SC's Type 616/16 90 HP engine was tailored for the 902, with a modified exhaust system, slightly lower compression ratio, new carburetors and air cleaners, and an oil cooler inside the fan shroud.  The 902's engine, known as the Type 616/36, produced five less horsepower than the 616/16, but delivered about the same maximum torque at 3,500 rpm versus 4,200 rpm for the 616/16.  For countries with lower speed limits such as the United States, the 616/36 engine proved sufficient and reliable.  And the Type 616/36 solved a second challenge for Porsche: by 1963 sales of Porsche industrial engines, based on the 356 Type 616, had dropped; but due to supply and production agreements Porsche needed to continue manufacture of these engines. 

902 Prototypes

Ferry and Butzi Porsche, during 901/902 development, circa 1964.  Image © Porsche AGBuilding a series of prototypes [pre-production test cars] gave Porsche executives confidence that their cars were nearly ready for production and sale.  Before 901 production commenced in September 1964, the Porsche Vehicle Research Department had also set aside chassis numbers 13328, 13329, 13330, and 13352 for 902 prototype cars.

902 chassis Number 13352 (902/11), was manufactured by Karmann in Osnabruck and delivered to Porsche on June 29, 1964.  In running condition by September 17, 1964, Number 13352 was initially equipped with a four speed transmission with ratios similar to a 356SC, and Teves brakes.   Registered with license S-UP 934 in December 1964, it was tire tested at Hockenheimring, Germany in late September and early October, and personally driven by Ferry Porsche to Wolfsburg October 7-8, 1964.  Number 13352 continued to be used for noise and damper test through June 1965; Porsche sold 13352 on September 17, 1965. 

902 chassis Number 13330 (902/10), manufactured by Hausele, was in running condition by October 2, 1964, using engine number 830001, four speed transmission, Goodyear 695-15 HE tires, and Teves brakes.  Registered with license S-UP 935 in December 1964, Number 13330 was tested at Monza, Italy that month.  In January 1965 Porsche conducted endurance and heater tests, and the suspension was further refined in February 1965; Porsche sold Number 13330 on October 29, 1965.

902 Research Cars

After the first production car, any car that needs an improvement is given a "running change."  Cars devoted to testing after production begins are called versuchwagens [research cars], rather than prototypes.  Porsche designated chassis numbers 13386 through 13397 for research testing of the 902.

Porsche 902 Versuchwagen 13394.  Image courtesy Dennis FrickNoted automobile restorer Dennis Frick restored historically significant Porsche 902 Versuchwagen Serial Number 13394, the oldest 902 known to exist today, now shown at prestigious events such as the Amelia Islands Concours d'Elegance.  Dennis provided information about Number 13394 that notes in part: "This prototype has several features not found on production 912 Porsches.   Its mechanical sunroof is operated by a crank handle, which employs spur and bevel gears, enabling the sunroof panel to lower and slide forward.  (The production 911/912 sunroof, in contrast, is electric; it lowers and opens to the rear.)  Because of its unusual sunroof design, this car has, concealed behind the headliner, hand-formed wooden platforms for the sun visors.  A similarly shaped block supports the interior mirror.  In the dashboard, three gauges with 356 style bezel are fitted.   Also in evidence is a hand-cut steering lock, suggesting that such devices were tested on this vehicle.  In the trunk are six sturdy hooks, two fastened to each of the inner fender wells, and two attached to the latch plate.  The hooks are held in place by sheet metal screws, indicating that this was the first car so equipped.  (A few very early production cars have similar hooks welded in position.)  Members of the factory vehicle research team active during the 901/902 development state that they often fitted the four cylinder prototypes with extra fuel containers in the trunk for long distance testing.  It is though that the six hooks were initially installed for this purpose."

"Additionally, it is believed that some long distance testing of chassis components was done utilizing this car, which has its original engine, number 821118.  The engine is an air-cooled, horizontally opposed, 1.6 Liter pushrod four cylinder unit producing 95 DIN horsepower, taken unaltered from the 356 SC."

"While the exact disposition of every 902 prototype is unknown, it is known that some were destroyed in testing, some were scrapped, and some were sold to employees. The advent of the longer wheelbase model (B Series) marked the end of this car's usefulness to the research department. Factory archive records indicate that it was sold in 1967."

Jurgen Lewandowski's book Porsche 901: The Roots of a Legend, notes that 902 chassis Number 13396 was the second Targa test car, undergoing the first extensive test drive with Rolf Hannes from the Test Driving department on June 9, 1965.  Although the idea of the Targa dated as far back as 1962, on August 11, 1965, Porsche finally registered the roof design with the patent office under file reference 1455743.

The Results

Compared to the 901/911, the production Type 912 vehicle demonstrated superior weight distribution, handling, fuel efficiency and range.  As noted by Jurgen Lewandowski in Porsche 901: The Roots of a Legend, "The decision to bring out a four-cylinder alongside the six-cylinder variant turned out to be the right one, because many buyers liked the shape of the 911, but did not really want that much power.  The result was no less than 6401 buyers opting for a 912 the year it was introduced; exceeding the sales figures for the 911 by more than 100 percent."

Research Credits and References
Thanks to the Porsche Factory Archive Department; Dennis Frick of Europa Macchina, Lewisberry, Pennsylvania, USA; Jurgen Lewandowski, Germany; and the Klassieke Porsche 911 & 912 Club Nederland for information included on this page.
Part 1:   Origins of the Type 901 and 902 Series >>
Part 3:   Renamed: The 901 and 902 become the 1965 911 and 912 >>
Coming soon: Part 4, Production of the 1965 912
PCA 912+912E Register LogoCFollow us on Facebook and Twitterontact the 912+912E Register >>

Rick Becker, PCA 912/912E Advocate
Pacific Northwest Region

Legal & Privacy | Sitemap | Contact PCA National
Copyright 2011-2015 Porsche Club of America Inc. All Rights Reserved.