Everything you need to know about Tiptronic
A trawl through automotive magazines and websites will quickly find often vociferous debates about the merits of manual versus automatic gearboxes, and nowhere is that more true than in the world of sports cars. Naturally, the 911 hasn’t been immune from such debates, fuelled in some areas by Porsche’s decision to equip some models only with the PDK transmission (introduced with the 997.2 generation), the 997 Turbo S and 991.1 GT3 being cases in point.
That’s a more recent issue, though, because our focus here is on the transmission that introduced a proper automatic (as opposed to the Sportomatic launched in 1967 – a manual ‘box with the clutch operated via a micro-switch in the gear lever) to the Neunelfer for the first time. Tiptronic debuted in a model that was already marking a generational shift for the 911 – the 964.
HISTORY AND TECH
Described as ‘revolutionary’ by Porsche at the time, the Tiptronic gearbox first introduced in 1988 was a four-speed electro-hydraulically controlled unit that was developed in conjunction with ZF and Bosch. A conventional torque convertor transmission, it appeared to offer the best of both worlds: left in ‘Drive’ it would shift ratios by itself like any other automatic, but flicking the selector lever to one side allowed the driver to indulge in manual shifting by pushing the lever forward to change up or backward for down-changes.
A display in the speedometer showed which mode/gear was selected. Yes, being just a four-speeder was a limitation and meant the spread of ratios was wider than was truly ideal, but Porsche countered this to some extent by equipping the Tiptronic ‘box with an ‘Intelligent Shift Programme’. Controlled by an ECU that monitored inputs such as vehicle and engine speed, throttle position and lateral/longitudinal acceleration, it could pick from one of five shift programmes that adjusted gear change points according to whether the driver wanted to cruise or extract maximum performance. And this electronic control brought other benefits, including the avoidance of over-revving by automatically upshifting at maximum revs, and preventing gear changes at inopportune moments, such as when cornering.
For our full guide to the Tiptronic gearbox, pick up your copy of Total 911 issue 202 in store today. Alternatively, order your copy online for home delivery, or download it straight to your digital device now.