Variable Cam position with a Diff

Frederic Breitwieser frederic.breitwieser at xephic.dynip.com
Fri Jul 3 12:53:44 GMT 1998


>Have I just answered my own question ?
>Maybe partly. 
>How do ya control the relative movement on this thingy while it is spinning
>around?

Yes, this is how a differential works.  When both wheels travel at the same
speed, the differential is effectly a spool, logically a rigid structure,
and your 3:1 ratio is a true constant.

When one wheel turns faster than the other, i.e. during a turn, then the
differential rotates within the differential housing to compensate for the
speed delta between the wheels.  The 3:1 ratio is then divided across the
two wheels.  This is one of the reasons why its so easy to spin wheels with
an open diff - one tire breaks free, the other tire holds and doesn't spin,
the the effective tire RPM of the spinning, free tire, spins at a much
higher RPM.

Using a smaller version of the differential (rear differential I mean) can
achieve the same thing.  By adjusting the relationship between the "free
wheel" and the "stuck wheel" you can control your timing.

And yes, you answered your own question.  I had to read the original post a
few times before I could picture it actually.


Frederic Breitwieser
Bridgeport, CT 06606

Homebrew Automotive Website:
http://www.xephic.dynip.com/

"When in doubt, use a bigger hammer"
-



More information about the Diy_efi mailing list