Power And Performance III Tuners Practice Test

Lower friction in the bearing system reduces the opposing torque on the shaft, letting it accelerate with less resistance. A ball bearing setup uses ball bearings to separate the moving shaft from the housing, dramatically reducing contact friction and oil-film drag compared to a conventional journal bearing. That reduction in friction translates directly to quicker shaft acceleration and faster spool. A conventional journal bearing turbo relies on sliding-contact bearings, which have higher friction and more drag, slowing spool. A water-cooled turbine housing helps manage heat and reliability but doesn’t significantly change shaft drag. A twin-scroll design improves exhaust flow and reduces turbo lag by optimizing pulses, but its main benefit isn’t reducing drag on the shaft.