Removing over 50% of the reciprocating mass pulling on the front of a crank and under driving the pully system will not damage a JZ engine especialy the 1JZ "Factors such as shorter stroke" come into play with the 1JZ the piston travels at a much slower rate and haves virtualy no imbalance measurable.
If you dont believe me run your 1JZ with a so called oem balancer then run it at the harmonic where vibration would be the highest on our engine, then do the same with an aftermarket pully tell me how much of a difference you feel in the engine vibration. Now compare the two in performance again there you will notice something.::dead horse::
Alot of specificaly designed race engines where they pull 5-10 X the power of the engine usually dont even run accessorys or even a crank pully they run everything off the battery and recharge it after the event being they would be concerned about a high strained engine completing a compatitions they if any thing would be more concerned if the myth was true.
http://www.unorthodoxracing.com/faq_pulleys.html
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 domestic 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. 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 making them look similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress noise from the engine accessories; 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 realize 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 B & D Series engines, Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's just to mention a few. 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 and frequencies of high amplitude. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as shorter stroke length, smaller displacement, piston dwell time, piston pin off-set, power output, etc., do determine when and how these harmonics and torsional movements occur. More importantly the actual tune of the engine, espcially with modified vheciles, is the biggest factor in potential engine damage. Poor tuning leads to detonation which is an engine killer that no damper can stop.
Again, there is a lot of internet hearsay about solid 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 our 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.
