AMS R35 GTR Race Pulley Install/Specs...

My first impression with this reply was to question the tone. Secondly, regarding trade school we are Red-Sealed Mechanics at AMS and have offered our fully balanced crank pulleys as has UR etc. for years with zeros issues on some of the industries most powerful builds.

I see that you have fallen to the fate to internet rumour regarding crank pulleys etc. Referring to poorly made old-school motors which are balanced from pulleys is a bad comparison. These motors were balanced with the pulleys! Most modern motors are fully balanced from the factory internally such as the Z32,Z33,R35. The rubber band on these factory units is commonly referred to as an “Isolator” .

Instead of reciting what is ‘common knowledge’ amongst accredited technicians in the industry I will offer up text from UR’s site

"[SIZE=“1”]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. [/SIZE]"

I hope this info will enlighten enthusiasts. As always we are here to answer any questions and/or rhetoric :slight_smile:

Rest assured your favorite ride is in safe hands and is awaiting several more Industry first offerings from AMS :slight_smile:

Regards,

Vuk@AMS