1978 Porsche 911 Turbo

Chassis No. 9308700291

Engine No. 6780301

Transmission No. 7800268

Famous for its minimal restrictions on engine output and aerodynamics, the Can-Am racing series served as an ideal proving ground for Porsche to experiment with turbocharging technology. Partnering with Penske Racing, Porsche dominated the 1972 and 1973 Can-Am championships with turbocharged versions of the 917, piloted by George Follmer and Mark Donohue. Building on this motorsport success, Porsche brought turbocharging to the road with the debut of the Type 930 at the 1974 Paris Motor Show. The first 911 Turbo featured a 3.0-liter flat-six with a single turbocharger, widened fenders, upgraded suspension, and the iconic “whale tail” rear spoiler. With a zero-to-60 mph time of under six seconds and a top speed of 155 mph, it rivaled contemporaries like the Lamborghini Countach and Ferrari 512 BB—while delivering superior practicality and everyday usability.

The early 3.0-liter models remained in production through 1977, but major updates arrived in 1978. Chief among them was an increase in engine displacement to 3.3 liters and the introduction of an air-to-air intercooler, boosting output in UK-spec cars to 300 horsepower at 5,550 rpm and 282 lb-ft of torque at 4,000 rpm. Porsche also fitted a revised rear spoiler to accommodate the intercooler, alongside improvements to the braking and suspension systems. The result was even sharper performance with 60 mph flashing by in just 5.4 seconds on the way to a top speed of 162 mph.

The 3.3-liter was, indeed, the emerging in-demand supercar with waitlists for all but the best regular Porsche customers whose ranks included one Alastair Robertson. Throughout the 1970s Robertson purchased four iconic Porsche models, three of them new. In 1973 he acquired a Carrera 2.7 RS intending to rally it but could not bring himself to do so. A year later the RS was sold and was shortly replaced with a 911 Carrera 3.0. Upon hearing of the new intercooled 3.3-liter Type 930 Robertson visited JCT 600 and placed an order for this 911 Turbo chassis number 9308700291. The other Porsche? A circuit-raced 356 Carrera four-cam.

The JCT 600 sales invoice and PCGB Certificate of Authenticity (CoA) reveal the order details. Robertson selected Grand Prix White, a color that first debuted on the Carrera 2.7 RS, with an electrically operated passenger door mirror, air conditioning, and Recaro sport seats. Perhaps his best choice that day was to select the en vogue red MacLachlan tartan interior. The rich wool fabric woven in red, blue, black, and a touch of green covered the sport seat inserts, rear seats, door panels, and rear side panels offering an incredible contrast to the monochomatic exterior livery. The invoice and Certificate of Authenticity both list the engine serial number (6780301), with the CoA also recording the transmission serial number (7800268)—remarkably, this carefully preserved example still retains both original components.

A statement from Robertson reveals that he took delivery of the car in February 1978. Under his careful 37-year stewardship, the car was not driven if rain was forecast, and “if when out, I came across newly chipped roads, I would turn back and find another route.” Quite the dedicated owner! He retained the car until 2015 and at that time stated that “The paint, panels, and underside are 100% original.” That year the 911 Turbo was sold via Tom Hartley with just 14,701 miles on the odometer (a scant 397 miles per year) to Rob Marsden of Surrey. While with Hartley, two separate service invoices record an engine-out service down to the head studs at BS Motorsport that totaled just under £14,000. During Marsden's ownership period the Porsche Club Great Britain member would have Precision Porsche Ltd. of East Sussex look after the car with engine servicing, shifter bushing repairs, new sunroof cables, new rear shock absorbers, finally treating the car to an “OEM look” stainless steel exhaust system.

Later, Robertson passed the well-kept, low mileage Turbo to the consignor—just its third owner in the past 47 years. After acquiring the prized Porsche, it was sent to Porsche specialist Charles Ivey in May of 2025 at 19,941 miles for a new alternator, battery, and four fresh and correct Pirelli Cinturato P7 tires fitted to its 16-inch forged Fuchs wheels.

Today, this right-hand-drive 3.3-liter 911 Turbo might very well be the best available on the market ticking all the right boxes. It is a matching-numbers example that features long-term fastidious original ownership and low miles accrued due to careful use. It wears its original coat of Grand Prix White over an interior color combination with Recaro sport seats that is among the most desirable imaginable. Its short succession of three owners is well documented as are the service visits to Porsche specialists, the most recent of which occurred in May 2025. Early 3.3-liter 911 Turbos are rare to find in such condition and impressive specification making this example a standout opportunity for collectors seeking authenticity, provenance, and performance in one exceptional package.