1938 LaSalle Production - GM Heritage Center

which increases its power output to 140 H.P., increases
its maximum speed and improves performance. Ethyl
fuel is required.
Pistons and Rings
Aluminum alloy pistons are subjected to a costly anodizing
process. This is a special electro-chemical bath
treatment which gives a gem-like hardness to the light
weight aluminum. Advantages, of Anodized Aluminum
Alloy pistons are: lighter weight, greater strength, and
greatly minimized wear and scuffing, particularly when
the engine is started when cold.
T-Slot,
Anodized
Finish, 4-Ring Piston
The T-slot type of piston is used for positive assurance
of uniform expansion and contraction. The T-slot
permits walls of the piston to expand freely at all
points, thereby fitting itself evenly and correctly within
the cylinder bore. This is impossible in the Invar-strut
type because such pistons are held rigidly at the struts
expanding unequally at other points.
Cadillac-LaSalle pistons are ground slightly out of
round, which is also important to uniform bore fitting,
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