Oil Distribution Optimization for Friction Reduction in a High-speed Racing Engine (CART)

The effect of oil distribution on journal bearing and piston friction and temperature was analyzed in a high-speed (CART) race engine, in order to reduce friction and improve reliability by optimizing the oil flow. Oil flow was measured with hot-wire sensors installed in actual engine oil feed lines, and piston temperatures were measured by thermistors using the electromagnetic induction method. The measurements were performed under firing conditions at engine speeds exceeding 15,000 rpm. Using the measurements, a well-balanced lubrication system specification was realized.