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18 November 2018

Material choises

Steel

Our steel con rods are fully machined in-house from our own specification 4340 material for increased strength and reliability (very low sulphur content below 0.01%)

Tool steel rods also available with an addition of Vanadium percentage for high horsepower and for customers with extreme engine requirements

All rods are shot peened using our automated process to increase fatigue strength and durability. The rods are balanced end to end within 0.1gramm into matched engine sets and are 100% magnaflux crack detected prior to final inspection

 

 

Material choises

Aluminum

On high horsepower engines, an aluminum rod acts like a shock absorber between the piston and the crankshaft. Without this cushion, the bearings may flatten, the crankshaft may crack, or the main caps will start walking/shuffling or even break. Using an aluminum rod ensures that all these components can withstand the stresses of a high horsepower engine.

When running an aluminum rod, your running clearances need to be adjusted as the aluminum rod will grow more than a steel rod.

You cannot run a press-fit pin on an aluminum rod, but for most applications, we recommend not using a pin end bushing, as the aluminum is an excellent bearing surface and bushings tend to come loose when the pin end of the rod is heated. We recommend you send your wrist pins to us for final pin fit.

Aluminum rods can handle sustained high rpm usage. Remember, it is heat cycles that shorten the life expectancy of an aluminum connecting rod. In some drag racing applications, aluminum rods have to be changed after only a few passes and in other cases, they have run for years or thousands of passes.

The only way aluminum rods are deformed or fractured either from an engine failure or past their end of life cycle.