Deutsche Dummheit - 1980 Interscope IR01 Porsche Indycar


During the 1970’s, German sportscar manufacturer Porsche had slowly but steadily begun dominating the world of motorsport. The flagship 911 model was a force to be reckoned with on any tier of GT racing and even saw success as a rally car. In addition, the company’s various mid-engined prototypes started issuing orders in the sportscar racing scene. Famous models like the 904, 908, 917 and 936 helped Porsche score countless victories, and cement itself as one of the most prolific racing factories.

The seemingly never ending stream of success gave Porsche an increasingly strong position in Europe at the time, but the firm’s American presence was eligible for a little aggressive expansion. Porsche was well represented in the main sportscar series, IMSA and Trans Am, but something was still missing. To truly make their presence known they had to compete at the country’s most prestigious event, the Indianapolis 500.

So in mid-1979, Porsche’s board approved a plan to tackle the 1980 edition of the Indianapolis 500. Porsche was in no mood to design an entire car from scratch, as their engineers had no experience whatsoever in the alien world of oval racing. With this in mind the company focused on finding a chassis partner, whilst preparing a suitable engine.

Porsche’s search didn’t lead very far. Initially Dan Gurney’s All American Racers was considered, but eventually the decision was made to forge an Indy partnership with longtime Porsche customers Interscope Racing. The team had seen success with Porsche’s 935 in the IMSA’s series, and also competed in Indycar with a bought Parnelli chassis. To top it all off, Interscope possessed an experienced ovalracer in the form of Danny “On the gas“ Ongais. The Hawaiian proved his versatility and blistering speed by scoring a win at the 1979 24 Hours of Daytona with the 935.

Interscope Racing and Danny Ongais were successful with Porsche's 935 in IMSA.

Interscope Racing and Danny Ongais were successful with Porsche's 935 in IMSA.

Porsche asked Interscope to build a new chassis to accommodate the brand new Porsche Indy engine, which would require some unconventional construction methods. Like all Porsche engines the unit would be a flat six type. In cars like the 911 this posed no serous issue, but an Indycar chassis was vastly different.

By that time the Ford-Cosworth DFX V8 had become the engine to have. One of the V8’s main advantages was its ability to be mounted directly to the monocoque chassis as a stressed member, owing to its shape. The flat six layout Porsche used was ill-suited to this, so Interscope had to fashion a separate tube frame “cradle” to support it.

Porsche's Typ 935 Indycar engine.

Porsche's Typ 935 Indycar engine.

Unsurprisingly, the meticulous Germans decided to simply derive the Indycar engine from the existing Typ 935 flat six already used in the Group 5 935 silhouette. In accordance with CART regulations, the unit was shrunk down to 2.65L (161 ci) capacity and featured only a single turbocharger. Like in the 935, the engine featured a unique partially water-cooled layout.

Porsche had found the cylinder heads of their fully air-cooled turbocharged engines to fatally overheat whilst competing in the European endurance races. Sensibly, the company incorporated water-cooled cylinder heads, with the rest of the block remained air/oil-cooled.

As with all Indycar designs, the turbocharger was mounted far back onto the gearbox.

As with all Indycar designs, the turbocharger was mounted far back onto the gearbox.

Preparations for the upcoming Indy 500 were coming along nicely, but Porsche couldn’t have timed their debut more poorly. America’s biggest open wheel racing category was in the middle of a bloody civil war. In a similar situation to the FISA-FOCA war raging in Formula One, Indycar racing had seen a conflict flare up between governing body United States Auto Club and the recently formed team’s association, the Championship Auto Racing Teams.

Starting in 1978, the two warring factions competed for dominance in American single-seater racing. Slowly but steadily CART swayed more and more teams and tracks to their side, with USAC’s influence decreasing. With most of the tracks conquered, CART took the Indianapolis 500 as its main battleground, as USAC was still maintaining control over the event. USAC and CART entered an extensive legal battle after USAC refused to accept CART entries at Indy, which CART won. In response, USAC declared the Indianapolis to be invitation-only, barring any CART members from entering the race.

Danny Ongais and the Interscope IR01.

Danny Ongais and the Interscope IR01.

Amidst the turmoil, Porsche now had to deal with USAC with extreme prejudice. The organization was thrilled to have a major manufacturer like Porsche enter the fray, but would not tolerate any sign of defiance.

On their best political behavior, Porsche lobbied with USAC to have their engine designated as a so-called “stock-block”. Contrary to CART, USAC’s regulations included a turbo boost advantage for stock-blocks, which were to be based on ordinary production engines. The loop hole allowed Porsche to modify the engine to accept 1.82 bar (26 psi) of boost, which saw power soar somewhere beyond the 800 horsepower mark.

In this configuration the engine was mated to Interscope’s new aluminium monocoque IR01 chassis. With the car completed, the team trekked to California’s Ontario Motor Speedway for a series of top secret tests. Ontario Motor Speedway had been built in a nearly identical layout and length to The Brickyard in an attempt to bring Indycar racing to the West Coast. So if the car excelled at Ontario, it would most likely also dominate Indianapolis.

With Danny Ongais at the wheel and the insanely powerful flat six in the middle, the unremarkable chassis lapped the 2.5 mile (4 km) oval faster and faster. During one of the secret tests, the brand new car shattered the standing lap record. Supposedly this incredible feat wasn’t just witnessed by Porsche and Interscope, but also by a number of spies from rivaling teams.

The Interscope's cramped cockpit.

The Interscope's cramped cockpit.

To Porsche’s shock and horror, their achievements at the Ontario tests were indeed known around the paddock. Indycar royalty A.J Foyt also got wind of the project, and started worrying about the competitiveness of his Ford-Cosworth powered car.

The Porsche’s higher allowable boost obviously meant it could produce far more power than Foyt’s DFX, which had not been designated as a stock-block. The presence of the lightning fast Danny Ongais further concerned him, so he decided to fight back.

Promotional poster for Interscope Porsche's 1980 Indycar effort.

Promotional poster for Interscope Porsche's 1980 Indycar effort.

Using his status as a respected senior racer, A.J. Foyt started lobbying with USAC to get them to withdraw the Porsche’s stock-block status, and lower its boost limit. His offensive troubled USAC deeply, as Foyt was one of the few superstar drivers to have remained loyal to the championship since the split. Losing him to CART was evidently not an option.

At the same time, the governing body wanted to appease Porsche. CART had been on the winning side of the war for a while now, and USAC desperately needed a high profile engine supplier. Porsche’s arrival had instilled hope that the German company would be able and willing to supply customer versions of the engine to other privateer entries.

Without resorting to idiotic things like subtlety, USAC plainly asked Porsche if they were interested in becoming a supplier. Porsche’s cold and dry answer was that they were perfectly capable of doing so, but had no interest whatsoever in actually doing it. Apparently completely oblivious to USAC’s current predicament, the manufacturer had slighted the cornered governing body in the clumsiest of ways.

The infuriating PR-fumble lead to USAC immediately imposing a lowered boost limit of 1.62 bar (23 psi). The change resulted in a massive loss of power, robbing the car of its record-breaking potential. Just 630 horsepower was left in the neutered flat six, which would make it a midfield competitor at best.

Porsche exploded with anger over the drastic decision. The resulting lack of power had rendered the mediocre Interscope chassis virtually unusable, making competing with it completely pointless for Porsche. They were only in it to win it, nothing else would do. With their competitive edge robbed from them, the company issued a simple but very bitter one page statement, announcing its immediate withdrawal from the Indianapolis 500.

The political drama left a bemused Ted Fields, principal of Interscope Racing, to pick up the pieces. Fields saw his Indy 500 effort fall apart right before his eyes, leading him to try everything to save it. After hastily conducting tests with reduced boost, he was convinced the weakened car could still be competitive.

However, his efforts to persuade Porsche to stay were all in vain. The proud company felt it had been embarrassed by USAC, and refused to deal with it any longer. In return Fields sued Porsche for breach of contract, and received an out of court settlement for his troubles. Sadly, he and Porsche had been wasting their time.

The Interscope IR01 Porsche was the company’s first attempt at cracking the lucrative American open wheel category. Porsche efficiently negotiated a competitive edge for itself, but was faced with a destructive political battle all around. The USAC’s weak position in the ongoing war with CART which Porsche had exploited to get its way turned out to have a dangerous flip side. From the other end A.J. Foyt struck back with an intense lobbying campaign, which left the helpless USAC in the middle.

The resulting situation was handled by Porsche in the most oblivious and heavy handed way possible. Forgoing all political sensibility, the stoic matter-of-fact Germans infuriated USAC by flatly refusing to build engines for them. As a result of their apparent arrogance and ignorance, Porsche was slapped upside the head by the desperate governing body. Inexplicably, this move took Porsche entirely by surprise. In the end the political minefield resulted in Porsche blowing itself up and leaving the series altogether.

However, the company was not left empty handed, as the Indycar development of the Typ 935 engine was later used to great effect in the all-conquering Porsche 962 Group C sportscar. A.J. Foyt got his way and reassured the dominant position of the Ford-Cosworth DFX, which left USAC was as the only real loser. Stubborn as they were, Porsche would return at Indianapolis at the end of the decade with a truly official car, the Porsche 2708.

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Comments (5)

  • great story and history lesson, promoted to the Best of USA! ^Joachim

      4 years ago
    • Thanks Joachim! Really appreciate it.

        4 years ago
    • what if Porsche actually ran the '80 Indy 500. I think the state of motorsport would be very different, and at the least that would have been a whole new chapter. who knew the roots of some of the Group C engine development came from this failed...

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        4 years ago