The first internal combustion engines did not have exhaust and intake valves open at the same time. When did it occur to somebody that overlap would improve performance, and when was this adopted by all engine makers? (I am not considering modern variable camshaft systems, just the basic fixed camshaft 2 valves per cylinder stuff).
when did valve overlap originate?
Jun 14, 2013
3 Replies
FWIW, valve timing issues such as overlap were discussed in a 1920's manual that can be seen at
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on page 95
Wow! Nice wealth of info on this ng.
afaik, it was this guy that started it all - the peugeot l45. the
4-cylinder 16 valve dohc motor with integrated head that offenhauser "used for inspiration" on their winning designs.Join the Discussion
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