Watch your oil pressure when you bring the motor down to an idle after a hard run. If it stays close to where it is when running at high rpm then you are OK. If it drops to 10psi or less when you bring it down then your temp is too high.
On my mine, the pressure drops to 10-15 psi at idle if the temp gets to about 240 running Mobil-1 15W50. Anything less than that and the pressure stays up. I put on a 3" X 12" oil cooler this year and so far it doesn't get above 235* and the pressure is good when coming down to an idle. Good luck.