[Paul Workman]

As most all ZR-1 drivers know, Mobil-1 is a product name, NOT a specific oil specification

Attached is a PDF file showing almost 3 pages of Mobil-1 products and their intended applications.

Their 15W-50 has the phosphorous/zinc (1200/1300ppm) that was recommended at the time our motors were built; intended specifically for flat tappet motors (liike ours).

For what it's worth, looking at the PDF file, it appears NONE of the so-called HIGH MILEAGE oils have the phosphorous/zinc at the 1200/1300ppm: ONLY 800/900 ppm and NOT specified @ the time the LT5 was in production.

Here's the MOBIL-1 that does have the "right stuff", AND specifically is formulated for FLAT TAPPET motors.


Mobil 1™ 15W‐50 1200 1300
Boosted, higher viscosity,
advanced full synthetic formula
designed for performance
vehicles.
For high HT/HS
applications. Racing and
Flat tappet applications. SN A3/B3

This week at the BG gathering will be Gary Cline and Graham Behan. It might be an opportunity to discuss it with the people who built the LT5!

It's up to the individual to decide, I guess. But, the phrase, "Your mileage my vary!" is especially poignant in this case, methinks.