The Facts About Unorthodox Racing Crank Pulleys
3) "How do Unorthodox Racing pulleys give me more power?"
Weight reduction is how we are able to increase Horsepower! Each pound of weight removed from the crankshaft is worth approximately 2.7HP and the gains jump even more dramatically with forced induction, nitrous, VTEC and increased RPM's. Only 15-20% of the gains from our pulleys come from underdriving. The diameter of each of our crank pulleys is reduced up to 20%. We tailor the exact amount of underdrive to each vehicle based on factory specified accessory performance. We fully maintain all accessory output minimums like air conditioning efficiency, power steering feel, and voltage (minimum allowable voltage 12v) even at idle with everything electrical on in the car. There are no adverse effects from using any of our pulley versions. Bolt them on and forget about them, then just follow your vehicles normal maintenance schedule.
4) "Is my crank pulley a harmonic/torsional/vibration damper or a harmonic balancer?"
People are getting their crank pulleys confused with the harmonic dampers found on some V6 / V8 engines. "Harmonic Balancer" is a term used loosely in the automotive industry. Technically, this type of device does not exist. The "balancer" part comes from engines that are externally balanced and have a counterweight cast into the damper, hence the merging of the two terms. None of the applications we offer use a counterweight as part of the pulley, as these engines are all internally balanced.
The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley that makes them look similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress natural vibration and noise from the engine itself, the A/C compressor, P/S pump, and alternator. This is what the manufacturers call NVH (Noise Vibration & Harshness) when referring to noticeable noise and vibration in the passenger compartment. It is important to note in these applications, the elastomer is inadequate in size and durability to act as an effective torsional damper. If you look at the pulleys on some imports there is no rubber to be found at all. We have samples of these, mostly from Acura/Honda, the Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's, to mention a few. This is not to say with our pulleys you will hear a ton of noise or feel more vibration from your engine compartment. Most owners who have installed our pulleys notice the engine actually feels smoother. This is result of replacing the heavy crank pulley with our crank pulley. NVH is variable and unique to every car. NVH will increase with the installation of an aftermarket intake and/or exhaust, for example. Think of OEM intake systems in newer cars, they use baffles and resonators in the intake to quiet all the intake noise. Aftermarket intakes eliminate these resonators and create dramatic increases in engine noise from the throttle opening and closing. So to most tuners, certain types of NVH can make the driving experience more enjoyable.
The purpose of a traditional harmonic damper is to protect against crank failure from torsional movement. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as stroke length, displacement, inline, V configurations, piston dwell time, piston pin off-set, power output, etc., do determine when and how these harmonics and torsional movements occur.
Again, there is a lot of internet hearsay about crank pulleys. When engine problems occur, too often people are quick to blame the pulley first, rather than taking the time to look logically into why there was a problem. We hope that after reading this you will understand the crank pulleys better.
6) "Will these pulleys cause premature engine bearing wear?"
This is a fear many prospective owners have and is a valid concern since we are dealing directly with the rotating assembly. Fortunately it is another urban myth with no basis in fact. The fact is our pulleys have the opposite effect on engine bearings. The combination of tight tolerances, precise quality control, perfect balance, and dramatic weight loss versus the stock pulleys reduces stress loads on your engine, extending the service life of your engine. Engine bearing problems are purely associated to poor engine maintenance, use of heavier than factory recommended oils, improper engine building practices (which includes poor balancing), excessively revving of engines when they are cold, and owners expecting their factory oil pumps to handle engine power outputs beyond 3, 4, even 5+ times the stock power levels.
