"Negative Overlap" or more commonly known as Pressure Balance cams

[EFISYSTEMS at aol.com]

Hi again,
      Rod stroke ratio is a key factor but is not a constant,,,,,,rod/stroke
ratio vs stroke plays a key factor in NA applications espesially in limited
airflow apps......it might surprise a person that a worse rod/stroke ratio in
a limited air app causes for a later intake closing event because of
stroke(only item being changed)...even though the piston doesn't dwell at the
top as long because of the rod/stroke ratio the swept volume takes
over.......more stuff to think of.......
-Carl Summers

In a message dated 99-03-28 23:06:00 EST, you write:

<< > air/fuel immediatly start filling the cylinder,,,,but such is not the
case in
 > any engine....the valve gradually opens and doesn't reach peak lift till
over
 > 100 degrees atdc...
 
 A quick point about 302 fords 454 chevys and other "short" rod motors. their
camshafts
 are designed to open the intake as quickly as possible because the short rod
tends to
 "yank" the piston away from TDC and "yank" the air column to get it
moving.... which
 is really hard to do with the valve half open!!!  sharpe
 
  >>