1938 LaSalle Production - GM Heritage Center

quently to cancel each other, the inertia forces must be
transmitted from one end of the crankshaft to the other.
This increases crankshaft and crankcase stresses, increases
the work which main bearings have to do, and
by increasing crankshaft deflection, causes the typical
straight eight high speed vibration.
Work which main bearings must do has been accurately
measured by Cadillac engineers. Taking a Cadillac
V-8 engine and a typical straight eight engine of practically
identical cubic inch displacement they found that
the total average maximum load or pressure imposed
upon the three V-8 main bearings is 173 pounds per
square inch, and on the five straight eight bearings 791
pounds per square inch. Five small bearings having no
greater area must do five times the work of three large
bearings. Operating smoothness, dependability and long
life is obviously greater in Cadillac V-type engines.
A long driven shaft has far more whip than a short shaft. \
A V-type eight cylinder engine is, by comparison |
with an eight-in-line engine, a twin four. Hence, it is
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