Honda invented VTEC to address the issue of compromise between street use and track use, by providing both a normal and a hot cam for each valve. Each pair of valves is actuated by three cams and three rockers, whereby the middle, hot cam and its rocker are totally detached from the other two cams until the engine management decides to call up stage 2.
The central rocker then gets locked to the other two, via amazingly tiny pins that are shifted into position by hydraulic pressure just as the engine hits 5200rpm. The idea is quite simple, but it’s pure genuius nonetheless.
What most sceptics and rival automakers thought was just another fancy acronym for variable valve timing turned out to be one of the most remarkable valve control systems ever employed by an internal combustion engine.
It was what gave the 1992 Honda Civic’s 1.6-litre B16 engine its ability to rev smoothly past 8000rpm and produce 100bhp per litre. How this powerplant, and its successor with 2-litre capacity, can spin to ever higher speeds (9000rpm) all day long with supreme reliability remains a mystery to other car companies.
