Oil pressure issues at Road Atlanta - real or imagined

[Steve Tinker]

Looking at the oil pressures, running @ 5,000rpm on the straits you are registering +/- 50 psi, and even under braking @ 4,000 rpm its still around 50 psi. But even before you hit the apex of the curves (and as you say especially turning right), the pressure immediately drops to 30 psi. So you have lost nearly 50% of your pressure due to cavitation. This would not be acceptable under normal track usage - in all the cars I have had at the track that had an oil pressure gauge fitted, I have never seen a pressure drop so pronounced. Sure, pressure drops with high oil temps, but 210 deg is not too bad for modern 5W40 non competition oils but I would imagine the oil temps would go up considerably if you were driving harder. If the temp sender was mounted in the sump pan, I would think the readings would be higher.
The old acceptable rule of thumb for oil pressure (once up to track temps) is 10 psi per 1000 rpm so your OK on the straitaways, but way below that on the sweepers. No wonder people lose their M96 / 97 engines on big sweeping tracks.....