Turbo timers are your friend.

 

Yeah read all about them and we had a good discussion on them here a few months ago. Really it boiled down to those remote start alarms having the turbo cool down feature and still allowed your car to operate like stock.

I just didn't realize you want a cool down period after normal driving. That seems odd to me. If I'm just cruising around town normally and pull in a parking spot and idle for 30 seconds how much does the turbo really cool down? and does that really make much of a difference. Apparently so from what Shodan says but I would just have never guested. Now if I've just been doing some nice WOT spirited driving then sure but all means I give it some cool down but even if I had some nice soft driving after the WOT driving I've considered that cool down too and then just shut it off.
Really wish my turbo had coolant ports. I'd hook those puppies up and never think twice about it again.

 

Well, coolant parts really assist when the car is shut down, and the transferring exigent heat travels from the turbine housing to the cartridge; right where the oil is sitting there, stayinga at a higher temp and "coking". Using BOTH a small cool down time AND water is optimal, but even with water, give a couple seconds. not long, just a few seconds, or a turbo timer.

Basically when you're not cooling down, you're burning the journal bearings, and thrust plates. You don't see it immediately, but over time, you'll notice a bit more blue smoke, turbo taking longer to reach desired pressure, etc. It's because you're burning the bearings in oil while its sitting there super hot, during your shut down.

I still use my GReddy turbo timer and have my alarm delayed so that it activates automatically after the 30 second shut down.