Honda RA168E

The Honda RA168E is the Formula 1 engine that Honda's research company developed under special commission from Honda Motor for the 1988 season, and the last of the 1.5 litre twin turbo V6 engines of Honda's second Formula 1 era. It belongs to the line that began with the RA165E of 1985. As the 1988 rules tightened boost pressure and the fuel allowance, the engine was given a higher compression ratio and a longer stroke to gain thermal efficiency. It is a water-cooled 80 degree DOHC V6 with 24 valves, displacing 1,494 cc with a bore of 79.0 millimetres and a stroke of 50.8 millimetres, weighing 146 kilograms and giving about 685 PS at 12,300 rpm at a maximum boost of 2.5 bar on a toluene and n-heptane fuel. It powered the McLaren MP4/4 and the Lotus 100T.