Lapping valves is a time-honored tradition in building engines that dates back likely to the earliest internal combustion engines. The time-honored process involves placing some valve lapping ...

Tons and tons of pages have been written on the Porsche-991-GT3-RS-is-missing-a-manual topic and while we ... namely a 997 GT3 RS lapping the Nordschleife almost as quick as the PDK machine.