CONFIDENTIAL Excepts From May 2012 Fluidampr B2B E-News ‘Sales Inertia - Fluidampr Support For The Sales Professional’ from the tech desk: part 2 - will fluidampr solve an out-of-balance condition? How To Balance An Engine With A Fluidampr To recap last month’s enews: the function of a Fluidampr performance damper is to protect the engine by reducing crankshaft torsional vibration. It is a common misconception that a Fluidampr, or any damper, literally ‘balances’ the engine (for simplicity, let’s assume we’re just talking about the damper controlling torsional vibrations and leave the internal v external balanced engine designs for a later date). Balancing the rotating assembly involves calculating the amount of rotating weight and reciprocating weight, putting it on a balancing machine, then adding or removing weight from the crank to fine tune the desired performance. Neglecting a professional balance job during an engine build or get it wrong and you can experience a lot of potentially devastating damage. This weight unbalance vibration happens once per revolution and has a low frequency. The torsional vibration that is the twisting and rebounding of the crank and is controlled by the damper is caused by the combustion cycle in each cylinder. It happens multiple times per revolution and has a higher frequency. CONFIDENTIAL Excepts From May 2012 Fluidampr E-News ‘Sales Inertia - Fluidampr Support For The Sales Professional’ Some prefer or need to balance the rotating assembly with the damper and flywheel installed. An engine builder must be aware that special instructions apply with a traditional Fluidampr. To control a broad range of harmonics across all rpms, the inside of a Fluidampr performance damper is comprised of a free floating inertia ring that shears thru a thin layer of viscous silicone. The bearing gap area is about the thickness of a sheet of paper on either side. Torsional vibration must be present to engulf the inertia ring and center it. This happens immediately on the first revolution. A balancing machine can not replicate combustion forces and produce the speed fluctuations to generate torsional vibration. On a balancing machine a traditional Fluidampr performance damper is never operating and the inertia ring will always show a slight false reading in the overall balance. If the engine builder is not aware of this, once the build is complete and firing you would be faced with an unbalanced engine! During manufacturing, both the Fluidampr housing and inertia ring are high speed balanced to spec on industrial quality computer spin balancers. Therefore, the proper procedure to balance a rotating assembly when using a Fluidampr is as follows: Cut-a-way of a Fluidampr performance damper without silicone. A balancing machine does not replicate the needed torsional vibration to center the free floating inertia ring inside. The bearing gap on either side is only about the thickness of a sheet of paper. Internally Balanced Balance the rotating assembly with no harmonic damper installed or the stock OEM damper. Externally Balanced If permissible on your Fluidampr performance damper, remove the hub/counterweight from the damper and install it on the crank when balancing. Example of an externally balanced Fluidampr with removable counterweight hub. If the hub/counterweight can not be removed, install the OEM damper with its counterweight. The Exception The exception is our CT Gold series dampers, featuring centering technology that will permit an engine builder to balance the rotating assembly with the damper installed.