In a message dated 9/20/0 2:08:07 PM, dhl@chelseamsl.com wrote:
<<The other thing that Buick did with the 3.8L (as I recall) is to
offset (angularly) the crank throws so that the pistons still each
reach every part of their cycle exactly sixty degrees behind the
previous piston (so the firing pulses are now regularly spaced in
time). The original 90-degree V-6 used the simple crank with throws
every 90 degrees, just like the V-8, so the torque pulses were spaced
90-90-180-90-90-180 -- just like a V-8 with the back two cylinders
misfiring -- instead of 120-120-120-120-120-120. THAT was a LUMPY
motor.>>
For those interested, the Buick motors mentioned are referred to as even fire
and odd fire V-6's.
Michael
|