APPLICATION GUIDE FOR DAMPERS

Pro Race Dampers

Crankshaft Torsional Vibration is the “Hidden Enemy” of Engine Durability and Reliability.

Below is the latest Application Guide for our Pro-Race Dampers.

Pro Race Dampers

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Note. This graph is a guide only. Modifications as simple as a change in the compression ratio will alter the amplitude of the crankshaft torsional vibration, therefore variables such as valve timing, crankshaft design, number of counterweights and main bearing journal diameter will also affect the amplitude of torsional vibration. A lightweight (lower inertia value) damper will have less “absorption” performance and will overheat the elastomer should the engine be used outside of its parameters. It is better to be over damped than under damped.

Engine Dynamometer Testing

Engine Dynamometer Testing

 

 

 

 

 

 

 

 

 

 

 

Engine Dynamometer Testing is used by leading damper manufacturers to ensure that their dampers are correctly tuned for each engine. The graph shows crankshaft torsional vibration across the full RPM range for a GM SB 385 HP, 350 cubic inch V8 engine.

With the GM 8-inch stock damper, a large amount of torsion occurs at approximately 6,000 RPM – it should be mentioned that OE stock dampers don’t address vibrations at high RPM’s, because most street engines rarely see the high RPM range.

For racing applications, however, this vibration could do serious engine damage, so PRO/RACER damper is tuned to drastically reduce this high RPM vibration, at the expense of a smaller vibrational peak occurring at about 3,500 RPM. This lower peak RPM is well below the speed relevant to the crankshafts natural frequency.