Porsche took its first major step in the evolution of its soon-to-be immortal 911 for the 1969 model year, extending the wheelbase of the new “B” series by six centimetres in the interest of improved stability.

The wheel openings were also modified to accommodate larger wheels and tyres.

Under the engine lid, the air-cooled flat six-cylinder engine remained at two litres of displacement but was built on a new magnesium-alloy case.

The 911 was now offered in three variations: the 110-horsepower 911 T, the 140-horsepower 911 E, and the potent 170-horsepower 911 S.

First introduced in 1967, the 911 S was the ultimate production Porsche.

It featured a reprofiled camshaft, larger valves, better porting, titanium alloy connecting rods, and a higher compression ratio.

Initially fed by two 40 IDS Weber triple-barrel carburettors, the 911 S was upgraded for 1969 with a Bosch mechanical fuel injection system which added an additional 10 horsepower.

Chassis upgrades extended beyond the str...