Crank Pulley
Single Belt Conversion
Underdrive
83% Lighter Than Stock
Unorthodox Racing Crank Pulleys are available in a number of
configurations.
Standard Belt Layout (Stock Diameter)
Many of our customers have asked for crank pulleys that do not
underdrive their alternators, power steering pumps, superchargers
and water pumps. Because of these requests we developed our stock
diameter crank pulleys. Many customers want the performance
benefits of weight reduction without any sacrifices, especially
audio enthusiasts as some audio competitions require voltage to
remain at a specific level. With our stock diameter crank pulleys
the alternator and other accessories spin at stock speeds with
NO underdrive. This is also important for stock or
aftermarket supercharger systems. These systems are either driven
off the alternator, air conditioning or power steering sections of
the crank pulley and now you can use our stock diameter crank
pulleys with these supercharger systems and have the same boost you
had with the factory crank pulley.st level with the use of the
factory diameter crank pulley.
100% of the power gains from the stock diameter pulleys comes
only from weight reduction versus the factory crank pulley. The
reduced weight allows for more power transfer to the drive wheels.
Any of our accessory pulleys that are listed individually can be
used in any combination with our stock diameter crank pulley or
purchased as a set. The stock diameter crank pulleys are available
in polished finish only.
Standard Belt Layout (Underdrive)
Our most popular crank pulleys, the ones everyone is familiar
with. This version of our crank pulleys increases performance
because they underdrive all the accessories (15-20% more power),
unlike accessory only kits out there that do not include the crank
pulley. This means one you air conditioning is on our crank pulleys
give you more power back to the wheels by not letting the air
conditioning compressor rob as much power.
However, we do not push the amount or percentage of underdrive
too far for two main reasons. First, it is important to keep
charging systems, air conditioning, power steering, and water pumps
moving fast enough for every day driving. Second, not much
horsepower is gained from extreme underdriving. We always keep our
underdrive percentage under 20% which is what allows us to maintain
factory specified outputs for all your accessories. Our testing has
found for most vehicle models you can upgrade your stereo to a
system of up to 600 watts (RMS) and not have any
charging problems.
For most applications all of the underdriving is done at the
crank pulley, not the accessory pulleys. This is done so maximum
weight loss can be achieved at the crank where most of the
horsepower gains are realized. The Ultra Series underdrive crank
pulleys are available in polished aluminum finish.
Single Belt Conversion (Underdrive)
Single-belt crank pulley conversions go even further to provide you
with the highest possible power gains. They are also a must in many
of the Acura/Honda engine swaps where the stock pulley will not fit
because of clearance issues. The single belt design only drives the
alternator . This makes for an extremely light piece that will
provide you with excellent power gains. Single-belt crank pulleys
are also perfectly streetable and can be used in many Acura/Honda
applications where the A/C and P/S are being removed for street or
track use. Our single-belt conversion crank pulleys are only
available in polished aluminum finish.
Features
- Real HP & torque gains across entire
RPM range
- One of the highest HP/Torque per dollar gains on
the market
- The broadest range of applications available
- Over 8 years of use in real world applications from street to
strip to rally to road course
- Better than OEM belt fitment & alignment
- Accessory pulleys available seperately for many
applications
- CAD designed & CNCd from 6061
Aluminum billet
