The cooldown temps you see depend on whther you are pre-turbo or post turbo...the heat reading will reduce faster on the pre-turbo than post-turbo because the pre-turbo is measuring the temp coming from the combustion chanber, which cools rapidly as you let off the throttle (reduce fueling), while post turbo readings indicate temperatures coming out of the turbo exhaust. The cooldown is to allow the turbo casing and bearings an opportunity to dissipate their accumulated heat to prevent oil coking for those of us not running synthetics, and even when I do switch over to synthetics (in anither 15K miles), I will still employ the cooldown procedure, reagrdless of what Banks says about it. On that note, my cooldown time running empty highway at 70mph and pulling into a truck stop is less than 1 minute on the Pyro, but I give it 2 minutes anyway; if coming into the neighborhood, the EGT's don't get high enough to worry about it (under 400*) so it only gets about 30 seconds. FWIW