Knowing that protection is just as important as performance, we partnered with Fluidampr to help develop an S2000 specific performance crank damper that offers better protection than OEM for their highly stressed and modified engines.

What is a Crank Damper?

Engines are internally violent machines designed to control vertically expanding explosions and turn them into useful torque.  Each explosion shoves the pistons into the rods, twisting a steel crankshaft.  We all think of steel as a stiff object but it is elastic just like rubber.  However, steel is nowhere near as elastic as rubber so if it bends too much, it fractures.  The crankshaft takes a beating as each rod journal is jerked from each explosion, bending it by fractions of a degree.  Multiply this by two firing pulses per 9000 RPM, resonations across several four-banger harmonics and into the bearings, valvetrain, timing systems and drivetrain.  We can all see the four-cylinder engine wobble in the engine bay or the stick shift “dance” at idle.  Imagine what going on at 8000+ RPM.

The OEM crank damper bonds a heavy steel inertia ring to the crank hub via a rubber O-ring.  The inertia ring absorbs much of these vibrations dissipating them into heat reducing the wear on the engine.  Over time, heat degrades the rubber and the OEM damper effectiveness is reduced, eventually needing replacement.  If left unaddressed, a worn damper will lead to accelerated wear and could lead to bearing or crankshaft failure.  Also, due to rubbers limited effectiveness to a narrow frequency range.  However, four cylinder engines have several harmonics frequencies that create wear on the engine that need to be dampened.  Additionally, modified engines can either shift the harmonic frequencies of an engine, reducing the effectives of a tuned damper, or simply create more vibration energy, accelerating wear by going beyond the range of the damper.  Performance rubber based crank dampers can use more rubber O-rings to target a few narrow frequency ranges, but they still have longevity issues as the rubber degrades.

What is a Fluidampr?

Fluidampr is a viscous type performance crank damper.  Instead of bonding a steel inertia ring to a damper hub via rubber o-rings, it suspends the inertia ring in a viscous silicone gel inside of a crank hub shell.  Silicone has a much longer life than rubber, proven by 1000+ foot pound torque diesel engines running 500,000 miles before replacing a viscous damper.  Also, the inertia ring is free floating with in the silicone gel allowing it to absorb vibration energy across a wide range of harmonic frequencies.  Vibrations travel down through the crankshaft, hub, and gel into the inertia ring.  The inertia ring absorbs the vibrations creating shearing forces within the gel and dissipating them as heat before they are reflected back into the engine.

Weightless Effect

A side benefit of having a floating inertia ring is since it is not directly connected to the hub via rubber ring, it has less rotational weight.  Centrifugal force and vibration energy center the inertia ring off the hub reducing the rotational weight on the crankshaft, potentially freeing up a few HP.  On our engine dyno we saw remarkable gains of up to 15 HP and 8 ft-lbs of torque.  Below are the results measured at 100 RPM increments on our engine dyno.  This would typically produce a very jagged torque graph, as seen with the OEM damper.  However, with the addition of the Fluidampr, the results show a much smoother torque and power curve.

Fluidampr vs OEM Crank Damper

The data above was gathered on an engine dyno, allowing us to measure in a much more controlled environment as opposed to a chassis dyno that is affected by outdoor weather, drivetrain, tire inflation etc.  We control the pull to 2 seconds per 1000 RPM via a dynamic load which enhances the “weightless” effect of the viscous damper.  The slower you pull, the more harmonics can stack up, supporting more rotational weight of the inertia ring as it dampens them from the engine.  We don’t run slow dyno pulls to gain an advantage, we do it for consistency.  In this instance it happened to improve these results.  Pleased with our findings, we wanted to back them up with another motor winding quickly through the RPM range.

The next dyno (below) is a fully built turbo motor on a Mustang dyno taken a few minutes apart.  The Fluidampr, which is red, is about 5 ft-lbs better at low and mid RPM as the turbo slowly begins to pull.  Once the turbo was on full boost, the rest of the pull was over quickly reducing the weightless effect of the damper.

Fully built turbo motor with Fluidampr Change

True S2000 Fitment

There are other performance crank dampers out available for the S2000, however the Fluidampr is designed specifically to fit the S2000 – it is not a modified K series damper.  The diameter is the exact same as the OEM and it will drive all accessories at the speeds Honda intended them to operate at.  The K series actually has a larger diameter meaning that a K series-based damper will overdrive the accessories losing horsepower.  We have also included the Honda hex indention so that it is compatible with the OEM crank bolt removal tool.  Additionally, we have also provided a 3-bolt mount on the front of the damper to drive dry sump systems or other performance accessories.

Engine Protection

We want to be clear, you should not buy a crank damper to gain horsepower.  The Fluidampr is designed to protect your engine by dampening larger and wider ranges of crankshaft vibrations.  Crankshaft vibrations accelerate wear on engine bearings, timing systems, valvetrain and can even alter valve timing.  Boosted or highly modified engines increase crankshaft vibration and engine wear.  Frequently tracked S2000’s spends more time at elevated RPM’s where crankshaft vibrations are at their greatest.  Specifically, on the S2000, the 4^th order harmonic skyrockets after 8000 RPM with the OEM damper.  Every time you go above 8000 RPM, the engine is trying to shake itself apart.  Using the Fluidampr is analogous to using synthetic oil, it won’t solve major problems, but it will extend the life of your engine and provide more protection in extreme situations.  If you still think we are full of it, below is a customer provided vibrometer reading taken off the S2000 motor.

Customer provided Vibrometer reading taken off S2000 motor
OEM damper on left, Fluidapr on right