1938 LaSalle Production - GM Heritage Center

The nine main bearings assure resistance to bending
forces while the two-inch crankpins and 2½ inch
journals are amply rigid against torsional vibration, or
twisting forces, because of the light power impulses of
the small cylinders and the small inertia forces due to
the short stroke. The short stroke also permits the
main bearing journals and crankpins to overlap by 6 /$
of an inch which adds further to rigidity.
A rubber torsional vibration dampener is included
in the belt pulley assembly at the front of the engine.
It is more compact than before and is added solely as a
refinement.
v
Because of the short stroke, the many small cylinders,
the rigid crankshaft and the nine main bearings, the
Syncro-Flex flywheel, as used on Cadillac V-8, is unnecessary.
Pistohs and Connecting Rods
Piston and connecting rod assembly has been specially
designed for the new Sixteen. The wrist pin is locked
in the rod and rotates in the piston. A lock screw in the
Small Piston
and Short
Connecting Rod
small end of the rod passes through a notch in the wrist
pin, thus holding the pin against the rotation of the rod.
This new design makes it unnecessary to rifle drill con-
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