At PRI, Daido Metal’s Dustin Kull told RET, “Our proprietary multi-boring technology is what is driving us to be successful in motorsport and also aftermarket applications. Daido [oil film/plain-type] bearings are currently used in NASCAR, IndyCar, Formula One and Moto GP, as well as the likes of Sprint Car engines.
“This technology is geared around reducing oil consumption,” he said. “It reduces oil leakage from the rod and main bearings, which in turn allows an engine developer to reallocate oil pump capacity.
“For example, some engine builders have been able to turn down the overdrive for the oil pump, which reduces parasitic loss. In other applications they have been able to increase valvetrain cooling provision or reduce oil viscosity, to increase power.”
Asked to explain the multi-boring process, Kull replied, “Multi-boring allows for the elimination of the crush relief. Using the conventional boring method [for each half-shell] there is an extra cut at the parting line. That is intended to protect the bearing from hard contact at the parting line in the event that you have a flexible housing, where it is going to pinch the parting line, or if you have cap shift – anything that would make the parting line stand proud and scrape the oil film off the journal.
“In the case of our design, we have what we term ‘micro waves’ in the boring pattern. Visible only under a microscope, the waves make the material at the parting line more conformable. So if, say, cap shift or housing deformation should occur, the bearing will still conform to the journal and maintain the oil film.”
He added that Daido has developed proprietary materials for its shells, which are application-specific. He also noted that the technology is a drop-in replacement that can offer engine developers new scope to improve performance.
He also reported, “We are now using a very interesting material, called Thermalloy, a metallic self-lubricating material in which a solid lubricant – mainly graphite – is evenly dispersed throughout various base metals. It is machinable and is used for high-temperature, low-friction, essentially dry applications. So we are using it for wastegates and oil-less turbo applications.”
Daido Metal provides engine bearings for many forms of high-end racing