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Crankshafts
A TYPICAL SCENARIO
For years you’ve been running a stock crank and have
never experienced rod bearing failure. You decide to
“step-up” and replace your stock crank with an aftermarket
brand. Immediately you encounter bearing scuff or total
bearing failure. This scenario happens often, much to the
dismay of the engine builder.
Looking from the rod, back up through
the main, you can see daylight, indicating
it’s a genuine Crower crankshaft with the
“straight-shot” oiling system.
The unique teardrop scoop and exclusive
Crower “straight-shot” oiling system
increases critical oil flow from the main
bearings to the rod bearings.
Entry holes for the rod feed are located at
the O.D. of the main, allowing oil to flow
equally and unrestricted to the bearings.
This is key to prolonging bearing life.
THE PROBLEM
On most aftermarket
brands the rod feed
hole is only drilled to
the centerline of the
main. This method
of drilling doesn’t
deliver enough oil
to the rod . Creating
a high centrifuge,
high pressure
zone at the main,
restricting critical
oil flow intended for
your rods. As engine
rpm increases this
centrifuge effect
gets worse, possibly
resulting in severe
crankshaft damage
or even total engine
destruction. Not
the performance
characteristics you
expected when
you switched to an
aftermarket brand
crankshaft.
THE SOLUTION
STRAIGHT-SHOT OILING
After extensive
research and design,
Crower engineers developed the straight-shot oiling system
and virtually eliminates bearing burnout and customer
complaints. It features two Crower exclusives, off-center
drilling and the teardrop design oil hole, which scoops oil at
the main and forces it into the rod feed hole. Although it’s
time consuming, we feel it’s worth it.
THE PROVEN FACTS
It has been proven time and time again, “the lighter the
parts, the quicker the throttle response.” This is no more
evident than in the components that make up the bottom
end of an engine. Reducing a crankshafts counterweight
mass is critical in getting quicker acceleration and
deceleration. It also alleviates stress and engine wear and
improves oil shearing in the pan.
PENDULUM UNDERCUTTING AND
LIGHTWEIGHT PIN WEB AREA
Smaller O.D. design places heaviest
mass closer to the center of the
crankshaft for the quickest engine
acceleration possible.
Crower’s “counterweight
correct” design produces
optimum counterweight
positioning for the best
possible bearing loading
and proper balancing.
The shorter,
narrower
counterweight
reduces total
overall mass and
has less frontal
area.
Crower’s exclusive lightweight
crank pin web area allows
the counterweights to be
pendulum undercut to reduce
weight without the need for
heavy metal balancing on most
applications.
44.3% less frontal area
improves windage and
oil shearing in the pan,
two external forces
that frequently disrupt
a crankshaft’s uniform
motion.
The “Klose’s Stress
Concentration
Reduction” distributes
stress evenly over the
entire overlap area.
CROWER’S
“Maxi-Light”
REVOLUTIONARY DESIGN
The Crower Maxi-Light crankshaft redefines the term “light
rotating mass” by attaining just the right ratio of a smaller
O.D. counterweight with an exclusive lightweight crank
pin web area. By lightening the crank pin web area we are
able to machine excess material from the center of the
counterweights without adversely effecting balancing. This
is Crower’s patented pendulum undercutting. Lighter than
any other crankshaft like it on the market, the Maxi-Light
is structurally just as strong and easy to balance. Although
competing manufacturer’s claim to have comparable
designs similar to the Crower Maxi-Light, consider the fact
that it takes much more than just scalloping out the center
of the counterweight to achieve the correct combination of
light rotating mass and proper balance. Crower pioneered
pendulum undercutting the counterweights back in 1989.
For technical support call 619-661-6477 or visit www.crower.com
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