Meanwhile, Porsche Motorsport’s legendary chief, Norbert Singer, was assigned to oversee the development of a diminutive 2.14-litre engine, and by the time he was finished, it was putting out a scarcely believable 500bhp, courtesy of some clever internals (we’re talking polished titanium rods and sodium-cooled valves) and a gargantuan KKK turbocharger slung out below the rear wing.
The result was an intimidating but mightily effective package that Herbert Müller and Gijs van Lennep managed to pedal to second overall at the 1974 Le Mans 24 Hours, and another second at the 6 Hours of Watkins Glen – beaten only by a factory-entered Matra.
Setting eyes on the RSR in the Goodwood paddock gave me my first bout of trepidation, the second being brought on by the news that no warm-up laps had been factored into the schedule. But before I could lose myself in worry, the remarkably laid-back team from the Porsche Museum were on hand to calmly talk me around the cabin. An experience that I’ve always found to be both fascinating and oddly calming.
Better yet, there were no wagged fingers and no warnings about me having to return their priceless artefact in one piece, just simple instructions: “The car starts with a traditional key; the clutch is smooth; if you want more boost, turn this gauge; oh, and if it catches fire, get out. Have fun.”
Oh boy did I have fun. Well, once I got the first couple of laps out of the way. Warming up behind the safety car, the engine felt recalcitrant, bogging then singing, bogging then singing, while the Avon cut slicks needed plenty of energy put into them before they switched on. But once the pace increased and I was able to summon the courage to keep the thing on boost, I was given a flash of its potential.
Unlike modern turbocharged 911s, which are more tractable than a JCB, I quickly found that the RSR’s carburetted engine responded best to a wide-open throttle and plenty of revs. That’s not an unfavourable attribute for a track like Goodwood or La Sarthe, but it forces you to be rather committed. Get it singing and it simply demolishes straights, depositing you in the next braking zone before you’ve had time to breathe.