Its suspension was new too, following approximately the old architecture but changed not just in spring, roll bar and shock absorber rates, but quite fundamentally in its actual geometry, though this was done as much with homologating race versions in mind as anything else.
Visually there was not much to tell between a Turbo and a Carrera of a similar vintage: the swollen wheel arch blisters at both ends were a giveaway, as was the rear spoiler design, but as the car was so dramatically different beneath the skin, Porsche chose to let its performance do the talking instead.
It was received with a blend of euphoria and fear. My antecedents could barely believe its punch, but there’s hardly a review to be read that does not issue stark warnings of the consequences of playing fast and loose with so much power. Seems odd now, what with even the most basic Boxster besting its output.
But in fact Porsche was not yet done with the Turbo. If the 1974 Turbo was an exploratory toe dip into fresh waters, the 1978 car was a knees-up bomb off the top board. By expanding both the bore and stroke, Porsche took the engine up to 3.3-litres and, critically, used another racing lesson and fitted it with an air to air intercooler, capable of dropping the charge temperature of incoming air by a colossal 50 degrees centigrade. Cooler air is denser air, denser air has more oxygen in it, more oxygen makes a bigger bang when ignited with fuel and more power results.
As a result Porsche was actually able to peg back maximum boost pressure a tad, raise the compression ratio from 6.5:1 to 7.0:1 to reduce lag and still produce a big, fat 300bhp – a number no road Porsche had ever even approached, even though it’s still less than half the output of the latest Turbo.