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Fluidampr 35 Percent Underdrive Atl Pulley only Steel Internally Balanced Damper Honda All B Series

$512.00 Sale:$435.20


Model #620601

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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 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.

Critical harmonic vibrations occur numerous times in a engine s operating range. Stock rubber and elastomer-type dampers are frequency sensitive "tuned absorbers", and work at only one critical frequency. In the case of a stock rubber damper, it is tuned for a factory engine s critical harmonic vibrations. If you change the mass of pistons, rods, or the crankshaft, you change the natural frequency of the crankshaft assembly; therefore, the stock damper is no longer tuned to the new frequency of vibration, and you may be headed for early failure of expensive engine components. Dampers also create heat while they work, and rubber is a poor dissipator of heat. This heat and the exposure to the elements deteriorates rubber, causing it to crack and change durometer, which then leads to inertia ring slippage, damper failure, uncontrolled torsional vibration, and costly engine parts breakage.


  • Control destructive vibrations
  • Reduces wear of critical engine components
  • Contributes to greater valve train and timing efficiency

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Who is Fluidampr?

Fluidampr was the result of the demand of professional race engine builders for a durable viscous damper technology designed for motorsport application. Under the umbrella of Vibratech TVD, Fluidampr was born in the mid-1980s. Today, they have provided racers with high-quality products that are applicable to their high-performance needs.

Designed for Motorsport Racing

With the competitive world of motorsport racing continuously growing, there was a need for quality crankshaft dampers that would help protect the engine. A powerful engine is useless if it is unreliable. This is where Fluidampr comes in. They provide a crankshaft damper that would be able to withstand high temperatures across a broad RPM range.

A Brand for Everyone

Using the data they gather from their racing experience, Fluidampr is able to create products that are applicable for all sort of high-performance application, which includes marine performance, custom hotrods, exotic vehicles, and even the military. 

Quality Product from the US

All their products are 100% made in the US, making sure that they could maintain their high level of standard consistently. The company uses technology to their advantage as they use various high tech tools and techniques such as Finite element analysis and 3D additive printing for their design.

Purchase Fluidampr at Vivid Racing

If you want to ensure that your engine stays reliable even with that added horsepower, then Fluidampr has the right product for you. They are a trusted brand by many enthusiasts and racers alike. To know more about Fluidampr visit Vivid Racing and check out their list of products that would fit your specific needs.


All warranty claims must be made with your point of purchase.

Limited Warranty: Fluidampr warranty extends to the original purchaser only and a copy of sales receipt must be provided. Keep your receipt. Fluidampr recommends to our customers that they have their Fluidampr products installed by a certified technician or engine builder as warranty does not cover installation errors. Fluidampr offers a 1 year warranty for defects in material and workmanship. Repair or replacement will be at Fluidampr's discretion. If purchased from Fluidampr: To obtain warranty service, call customer service to receive a return authorization number. Returns must include the RMA#, description of the problem and a copy of the purchase invoice/receipt. Returns without an RMA# will not be processed. Customers are responsible for freight charges to Fluidampr. If product is found to be faulty, Fluidampr will pay UPS Ground Freight when returning the product to customer. THIS WARRANTY DOES NOT INCLUDE AND IS NOT LIMITED TO THE FOLLOWING: Failure due to improper installation or maintenance. Loss or injury incurred from use or operation of products. Misuse, abuse, modifications, or unauthorized repairs. Removal or replacement cost. Cost incurred due to downtime of vehicle. Damage to other engine or vehicle components. Normal wear and tear. Use in racing applications or competitive purposes. Fluidampr limited warranty coverage is subject to change due to uncontrolled circumstances with or without notice.

Fluidampr products are guaranteed to be free of defect at time of shipping.