Just ran across this article relating to Porsche.
"Porsche's recommendation in hand, our initial analysis from 2005 and
2006 found that all recent SH/SJ/SL formulations of Mobil lubricants
tested, including Mobil 1, have had similar 0.12-0.14% Zn and P
content, which we think is a good thing, but looking closer, Mobil 1
0w40 had somewhat less Zn and P, at 0.10%. Current SM formulations are
at the 0.10% level or less. This confirms the industry wide trend of
the reduction of Zn and P from motor oils, with the eventual reduction
to 0.06-0.08% or even worse, the elimination of these additives, which
are essential to an aircooled Porsche engine's longevity."
"........................... Prior to the new CJ-4 API standard for
diesel oils, we found most of the CI-4 15w40 and 5w40 oils to have
excellent levels of Zn and P. We did observe Mobil, among other
manufacturers, beginning the use of boron in their oils as a zinc-free
(ZF) anti-wear additive in various CI-4 and SL formulations, but
always with high Zn and P levels, above current API limitations."
"What motor oils had the 0.12% levels of zinc and phosphorus
recommended?
The current API standard is SM, and calls for 0.06-0.08% Zn and P. The
new CJ-4 standard which supercedes CI-4 calls for no more than 0.1% P.
Some of these reformulations have new zinc-free anti-wear additives,
but we still think a target of 0.12% is ideal for Zn and P levels as
documented by the 1977 SAE Journal paper titled "Cam and Lifter Wear
as Affected by Engine Oil ZDP Concentration and Type", which evaluated
the performance of these oils in various fleets around the country
over the span of many years.

Name                                 Vis     P (ppm)    Zn (ppm)  API
Type

Amsoil HDEO                    5w40       794          1081     SYN
Amsoil Series 2000 Racing 20w50    1014         1123      SYN
Amsoil V-Twin/MC              20w50   1193          1281     SYN
Castrol GTX                       20w50   1157          1422
DINO
Castrol GTX High Mile        20w50   1248           1382     DINO
Castrol Syntec                    5w40     786            918
SYN
Castrol Syntec                    5w50     921            914
SYN
Castrol Syntec Blend         20w50     937            916     SEMI
Castrol Tection Extra         15w40     965          1094     DINO
Chevron Delo 400              15w40   1191           1622     SYN
Delvac 1300 Super            15w40    1380          1702     DINO
Exxon Av Oil                    20w50      702             32
SEMI
Exxon Superflow              20w50      717            848     DINO
Ford Motorcraft                  5w20      545            848
SEMI
Harley Davidson Syn3      20w50     1081          1182     SYN
Kendal GT (Vintage)        20W50     1229          1415    DINO
Kendall GT                      20w50       904          1233
DINO
Mobil 1                              0w40      808           976
SYN
Valvoline All Fleet Plus      15w40     1110        1232     DINO
Valvoline Durablend           20w50      566          732     SEMI
Valvoline Max Life             20w50      691          879     DINO
Valvoline Prem. Blue         15w40      1314       1838     DINO
Valvoline Synpower           20w50        605         689    SYN
Valvoline VR1                   20w50      1085       1293    DINO
Valvoline VR-1 NSL           20w50       835         976    DINO
Valvoline VR-1 NSL           20w50       842         962    SYN
Power Service Oil Extender              3567       4945    O/A
STP Blue                                        1704       2436    O/
A
STP Red                                         2115       3932    O/A