fan spacers have a large bearing surface and are machined
to a soft radius. This reduces point-loading, which is the
most common cause of stress cracking on the fan center star.
This is why we require that a Flex-a-lite spacer is used with
our fans. Flex-a-lite fan spacers are machined from aluminum.
fans work best when they are 3/4 in. to 1 in. from the radiator's
surface. Whenever you remove an original equipment fan clutch
from your engine, you need to add a fan spacer. This will
bring the fan back into the "sweet spot" in the
fan shroud opening.