wross996tt

I know cool down (actually idle for at least 2 minutes) for a Turbo is a "must"...not sure if this is also true for an NA (I understand why for a turbo, but do not know why for an NA?).

Eli K

Not the same, and not as critical, but probably better for the car...

TD in DC

Yes, this happens with the 3.6 at the track once in awhile. As far as I can tell, cool down has little to no effect on this. I find that it happens after I have a particularly good run. My car never really runs very hot (it stays between the 1 and the 8 even on the track), but it will smoke a little upon startup after a very good run (doesn't sound like as much as your friend's car does). It also puffs a little puff of smoke right between T1 and T3 at VIR, nearly every time. I have seen many, many 3.6 996 motors do this, and I have talked to mechanics who say it is nothing to worry about. It never does it under normal street driving conditions.