Having been very successful with turbocharged cars in the 1970s, Porsche returned to Formula One in 1983 after nearly two decades away, supplying water cooled V6 turbo engines badged as TAG units for the McLaren Team. For aerodynamic reasons, the Porsche-typical flat engine was out of the question for being too wide. The TAG engine was designed to very tight requirements issued by McLaren’s John Barnard-he specified the physical layout of the engine to match the design of his proposed car. The engine was funded by TAG who retained the naming rights to it, although the engines bore “made by Porsche” identification. TAG-Porsche-powered cars took two constructor championships in 1984 and 1985, three driver crowns between 1984 and 1986. The engines powered McLaren to 25 victories between 1984 and 1987.

Porsche returned to F1 again in 1991 as an engine supplier, however, this time with disastrous results: The Footwork cars powered with the overweight double-V6 failed to score a single point, and failed even to qualify for over half the races that year; Porsche has not participated in Formula One since.

Porsche attempted an Indianapolis 500 entry in the late 1970s with a turbocharged 911-based engine in a bespoke car for Danny Ongais and the Interscope team; failure to agree turbo boost levels with USAC meant that this was shelved, although the engine later became the basis of that used in the 956 and 962. Porsche returned to CART in 1988 with a turbo V8 in their own 2708 chassis but this did not enjoy any success and a March chassis scored their only wins. The Derrick Walker owned and managed team was then sponsored by Quaker State and the drivers were Italian Teo Fabi and American John Andretti.