There are many benefits engineered into an aftermarket block that will benefit your performance and racing effort. When a racer researches block features, they have the mindset to study strength, strength, and strength.
When doing their homework on advertised block strength, improved ductile iron casting material, extra-thick cylinder walls, and increased deck and main web thickness are a racer’s shopping priorities. As you dive into Dart Machinery’s list of block features, you will notice a lesser-known bullet point titled “true priority main oil system.”
Priority main oiling is a specialized oil circuit upgrade that Dart includes with its domestic block designs. From Dart’s Iron Big M-series to the aluminum and billet blocks, the oil delivery path is changed to be routed first directly to the crankshaft’s main bearing.
An OEM block typically delivers oil from the top-end down, with the cam, lifters, and top-end receiving oil from the oil pump first. Without considering extreme performance, this is a much easier machining process for a factory block.
Why Change The Oil Routing?
With the high demands within a racing application, the bottom end of an engine can generate high heat levels. The priority main oiling route ensures that the critical crankshaft, main bearings, and connecting rod bearings receive prioritized lubrication, which also lowers temperatures in the engine’s bottom end.
Crankshaft bearings may become starved of oil and ultimately lead to engine failure.
“Oil volume demands are reduced, and the most critical areas of the engine are provided with the best level of protection first. Also, keep in mind that priority main oiling is not detrimental to the upper engine components or valvetrain, as their oiling needs are much less,” says Kyle Scheel, Dart Sales and Technical Representative.
Oil Technology Adds To The Equation
The improvement in oil technology itself plays a role with priority main oiling. In the past, 20W50 racing oil was heralded as necessary to stand up to the abuses of a racing application.
“Now, it’s not uncommon to see zero-weight oils and really tight clearances,” says Jeff Lake, Dart’s resident engine builder. “Oils are better than they have ever been. Engine builders are running tighter bearing clearances with modern, thinner oils. With these oils, you can move more oil volume with less effort.”
Oiling improvements are in additional locations, as well. Dart also redesigns oil gallery diameters to add block strength while not hindering oil flow volume. Oil crossovers in the lifter valley also have experienced conception changes.
With reengineering, casting, and machining of blocks all under Dart’s control, the entire block production and finishing process at Dart can easily develop future improvements to internal components in quick order.
When it comes to containing extreme horsepower with an engine block, further evolution in engine hardware and oil technology will certainly impact the design features of future Dart blocks when the next “eureka” moment is refined by their research and development department.