Ross Racing Harmonic Balancer with Crank Trigger Wheel

So a few people are interested in a proper crank-trigger pulley for Z32. The benefits of running a crank trigger rather than cam angle sensor (as per factory arrangment) are much more consistent crank position signal, which in turn allow you to really optimise performance via tuning the ignition timing.

Compare these two graphs below (taken from kickerzx' post on twinturbo.net)

The first is running a conventional CAS and as you can see the engine speed (top line in green) graph is very scattered



In this second pic you can see the engine speed graph is much more linear due to more consistent crank position signal from the crank trigger



I've been speaking to Ross Performance about having a trigger balancer made up using their Metal Jacket harmonic balancers and this is what we've come up with...

The basic features of the harmonic balancer are

• High carbon steel hub / pulley units
• High carbon steel damping ring, fully bonded using an anti-vibration, anti-tear natural rubber
• Damping weight optimized for much higher RPM and power level over an OEM unit
• Aerospace grade anodized aluminium power steering pulley
• OEM diameter water pump/alternator and A/C pulley to maintain optimal belt wrap
• Under driven power steering pulley to protect power steering pump at high RPM
• Lightweight anodized aluminium timing disk
• Laser etched 360° timing marks
• Steel components corrosion protected with a hot phosphate coating process and a high quality matte black paint finish
• Uses grade 10.9 or better hardware
• Complies with SFI spec 18.1

They are lighter than a stock balancer while still absorbing harmonic vibration from the crank shaft. A harmonic balancer is recommended over a non-balancing pulley, especially on high HP motors, as Each time the air/fuel mixture inside a cylinder is ignited, the combustion that occurs creates a torque spike that is applied to the crankshaft through the piston and connecting rod. This torque spike is so severe that it not only turns the crankshaft, it actually twists the crankshaft ahead of its normal rotation and then the crankshaft rebounds. This twisting action is known as torsional vibration. When these torque spikes and forces get into phase with the natural frequency, critical torsional harmonic vibrations occur and can be seriously destructive to the bearings and the crankshaft. Dampers are designed to control those destructive vibrations" (credit to Z1 motorsports for that explanation).

In addition to the above each balancer will be fit with a 24-1 toothed trigger wheel that is compatible with popular link, vipec, haltech etc ECUs.

Please note the pic below is of an RB series balancer (as they won't make an Z32 units until we order) and should be used as an indicative reference only.



Some things you need to know....

Obviously this will require a Hall Effect sensor and mounting bracket. It is my intention to have a suitable bracket CNC machined and to offer these as a package with the sensor at a later date. I need to have a balancer before I can get the bracket machined.

You will also need to use a Cam-Sync if you want to maintain sequential fuel & ignition. The easiest way to do this is by installing an AEM trigger disc into your factory CAS. I can do a group buy on these at a later date, too.

The cost on these per unit is $936.76, however for an order of five we can get them for $871 each. Please note that payment will be required in full should you wish to participate in the group buy, and that no refunds or cancellations will be accepted for any reason as your financial commitment is my financial commitment.

I have three keen buyers from discussions away from the forum; we need another two (or more) buyers to make this happen. This won't be for everyone, but if you're wanting to bring you Z32 in to the 21st century then it might just be for you...

Please indicate your interest, or fire away with any questions, below.

 

I've priced up for metaljacket series which have water pump & alternator, air con, and power steering as that will suit the majority of end users.

If you're after race series with no aircon pulley I can order that too, it'll be approx $50 extra.

 

Awesome and they'll 100% be black

 

Hey guys; have contacted Ross re pricing in race series (no air con pulley) dampers. Will post when they call me back tomorrow.

 

At best it's approximating the timing based on cam position (it can't know crank position).