JC,
You have not indicated the way you use your boxster. The prescription for a daily driver and a track car are black and white, oil and water. One needs a low viscosity oils with lots of additives (detergents, acid neutralizers) the other needs exactly the opposite.
You also did not specify your car, year, motor.
Finally, i have no idea what the 80,000 psi is - maybe a film strength on some test, but its not a normally printed specification.
The best compromise is really very simple: Any A40 certified oil. They will all be 0w40 or 5w40 with ACEA A3/B4 and lots of additives. Not ideal for track, but OK in typical new engines, and great for all other uses.
brand is less important than one would be led to believe - there are only a handful of base oil makers and additive makers. The blend matters, yes, but.....
As to ZDDP - for old flat tappets, yes. For racing or break-in oil, yes. For street? Meh. I do regular oil analysis at a lab and can confirm that the major brands, under normal use, hold up perfectly well and do a terrific job. Pay more attention to: changing it sufficiently often that acids and water do not accumulate as they will. This is also reduced by continued operation about 212 degrees F - like 20-20 minutes after complete warm up - and all that stuff boils off. The absolute worst situation for oil is to start a car up 3 times a week and drive it 10 minutes to the golf course (or whatever) and 10 minutes back. By the way, this wort of driving probably benefits from a 0w20 with huge additives - death if ever run at WOT and hgih revs..... the inherent trade off.
So, go to Wally World, buy whichever well respected brand of 0w40 / Porsche A40 is on sale, and move along. Truly.
G
Grant
gee-lenahan-at-gee-mail-dot-com