I've noticed we all like to talk about cam profiles and camshafts. Most of the discussions revolve around today's camshafts. It is interesting how the early engine designers did not pay much attention to cam profiles. Some of the earliest engines did not even have an intake cam; only an exhaust cam that opened the valve at BDC and closed at TDC. It always amazes me how mechanical devices develop over time.
I have lunch with ISKY everday , cant remember my name but remembers what time the sun came up on this day 65 years ago
It took a while for cam design to get sophisticated.... read about a 1920s motorcycle racer in England who was testing his bike for top speed when it suddenly picked up 2 or 3 MPH. When he stopped he found one of the valve springs had broken and the broken ends interlocked so it kept working, but weaker. He figured this caused enough valve float to keep the valve open longer so he went home and made a longer duration cam. Another guy designed his own cam on paper, cut the lobe shape out of cardboard, glued it to the cam and reshaped the lobes with a file. This was for a motorcycle too. Quite often when you get the truth about an early cam design it was copied off someone else's. The famous Duntov cam was done this way (how did he come up with a hot cam in a few days, he copied someone else's). A lot of guys got their start copying Winfield's cams or Miller or Offenhauser racing engine cams. Maybe Isky can tell you about this, it would be interesting to know the origin of some of the early cam designs.