Danny Williams

The Helical Camshaft - as mentioned above. There is also an earlier,simpler form of a variable duration camshaft (as listed below in the "patents" section). I have also come up with many others varieties of variable valve timing systems but which are not patented. Some of these have reached the running prototype stage.
Also as mentioned above I have a valid solution to the age-old (Da Vinci made one of the earliest efforts) to the variable gear puzzle.