I was noticing that the catalytic converter sits just a few inches below the turbo housing and exhaust temps reach 1300F+. When we shut down our beloved MINI's, all that heat rises and bakes the exhaust turbine and probably the bearings even if you idle a few minutes before shutdown. I can't believe that the turbo even lasted the 66,000 miles I've clocked on mine. It seems like we're all driving a ticking timebomb. I hope I'm wrong. BTW, I always take it easy on the engine when I'm close to my destination and change and monitor the Mobil1 0w40. Paranoia? Maybe.
You don't have to worry about it, the turbo is water cooled, and there's a pump that pumps coolant thru the turbo on shutdown till it cools. So, don't worry about it. Because of the cooling setup, you also don't have to let it idle before shutoff either.
I recall all the Subie people with turbo timers that didn't need them. The cooling system recycles the coolant through the system, without a pump, until the engine cools down.
fngolfer; You can hear the electric motor on the circulator running after the radiator fan shuts down. The circulator will run for a period of time and then will automatically turn off. This unit circulates the water through the turbo bearing until all is well...
Thats all fine and good, I agree with what has been said. But taking it easy a block or two and let the engine and turbo stabilize is not a bad idea. This will cut down on thermal shock.
No real thermal shock as the coolant is not "cold". It will simply cool down gradually with the coolant. BUT it can't hurt to take it easy as it would mitigate the coolant rising in temp from the engine just sitting there.
It does not matter! The turbo doesn't get that hot in normal driving anyway, and unless your foot is to the floor going up a several mile long driveway to your house, the turbo is already cool. Even if you just came off the track, the cooling system has the turbo's heat under control - that's the beauty of water cooled turbo. Relax, just drive it and let the car's systems handle it the way they were designed.
Ok I am not trying to disagree with you. I am not talking about normal driving. I am talking about spirited driving where you are banging up against the red linen. Yes the water is cooling the turbo but driving it at a normal pace or letting it idle for a minute is a very good practice. This goes with any car but twice for a turbo. By giving it time to stabilize you are allowing the heat to even out. Drive a turbo hard and look at it with a pyrometer you will find some parts are very hot even on a water-cooled turbo. Your just helping prolong its life.