Tyler, thank you very much for sharing your info with us!
I apologize to Mr. XFire for doing a hi-jack job on your thread.
It's just that this whole cooling system issue is making me think twice about what wisdom GM brought to the table.......most Z owners certianly do exceede 5k rpms with their cars I would think.....or at least I know I do when I'm doing the twisties with mine....again I apologize for the hi-jack.
Tom