Variable Cam Timing, etc...

[ShempMoDin at aol.com]

Alfa Romeo used a mechanical variable cam timing device for a few years that
was as Ed Hernandez describes.  It was an oil-pressure driven sprocket on the
intake cam.  I have it on my 81 Spider that I'm about to part out.

Also, regarding solenoid driven valves, I recently read about a new project
(don't ask me where) where they were having some success with this.  The
twist was that rather than having a solenoid open the valve and a spring
close it, they used two springs that, at rest, hold the valve at the midpoint
of open and closed.  Two solenoids were used, one to open it fully, and one
to close it fully.  Apparantly, this method reduced the total stroke needed
on each solenoid, and made it possible to use more efficient solenoids.  

- Paul Witek