Re: high oil temp 496 ho
The most oil temperature susceptible parts are the engine's crank and rod bearings. The water cooling system would go on fine, but the oil would take it on the chin if there were problems here.
Also, does the owner guarantee they are using synthetic oil as recommended?
From driving an Infiniti G35 Coupe with all the sport goodies, I've learned that there are
a number of newer engines that have susceptibilities to high oil temps, while water coolant temps stay quite normal. Time and time again,
it comes down to the bearings, their health and how hard you drive. If you run and gun, the word on the street with the G35 and Z car crowd is "get an oil cooler". Your typical commuter wont see a problem.
Other affected vehicles: C6 Corvette and BMW 330. What we have is high oil temps and normal coolant temps, with liability down near the bearings. The 'fix' is a quality oil cooler and synthetic oil. Bearing failures are becoming more common. Rumor is that manufacturers of bearings to the auto industry were forced to 'green up' their manufacturing process, and some harder materials used in bearings have been removed. A small percentage of those with H.O. version of certain engines with a tendency to push 'em are the ones who notice the problems. Most don't notice, or most don't push hard enough. Many just have older/harder bearings. So, we have signs of bearing failure, or signs of oil effectiveness being reduced to the point of internal failure, starting at the bearings. 290? Wow, that is believable, because that is in range of the high oil temps related to bearing issues. 260 to 290 or higher has been reported.
And what-do-ya-know, ya got a 2007 motor. Fits the bill. Heat down near the bearings. High oil temp. Increased wear. Reduced oil performance. Normal cooling temps. 
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