Kipper: as I have been an engineer involved in the designd and applications engineering for both ball and sleeve bearings, please, Please PLEASE tell me how to "preload a sleeve bearing"??????? Especially when sleeve bearings are NOTORIOUSLY INTOLERANT of metal-to-metal contact..(BTW:most turbos are sleeve bearing equipped because ball bearings have a hard time tolerating the speeds and temps of a turbo) ..
Motomitch: Yes, they have. But the ones you refer to were DESIGNED for that type of use in mind. This application is an automotive turbine housing used in a turbocharged application. The ONLY axail and radial thrusts it was designed to absorb/withstand are due to those generated by gas pressures - not the cutter reaction loads generated by machining.
Regarding oil pressure: idle pressure is one thing, off idle, cruise and WOT (wide open throttle) are totally different.
My 350 chevy idles at 20-25psi but pops up to 60psi as soon as you get over idle. My turbo Mustang back in the 80's saw a minimul of 40 psi and went higher when hot and at higher speeds.
Essentailly, the oil pressure that engine reaches is a function of the pump capacity, the speed of the pump/engine, oil viscosity and the loss factor due to clearances in the engine. The TPS signal is absolutely irrelevant to relief valve modulated, mechanical oil pressure pumps.  |