[chbot] Filter

[Marshland Engineering]

After quite a few chats and emails, the problem has become clearer. In some
way it may not really a filter issue. For a 4 stroke engine cam, there are
basically 4 components, base circle, up ramp, over the nose and down ramp back
to the base circle. 

So we have 0 velocity, acceleration to the up ramp, constant velocity,
deceleration, stop (over the nose) acceleration, down ramp, deceleration and
back to 0. 

The figures to look for are the acceleration. If it is too high then the
valve/valve strings etc loose contact with the cam. 

The figure for acceleration (from memory) is 0.008" per degree or .2
mm/degree.  This is what I want to measure/compare. 

Here is some info on it.
http://www.profblairandassociates.com/GPB_4stHEAD_ValveLiftDesign_hmb.html

Basically I have several different cams and want to measure them all and
choose the one with the most gentle profile. 

Cheers Wallace.