Passenger car and truck oils are formulated to reduce emissions and provide longer drain intervals. This has been done by increasing detergents and reducing anti-wear additives, but your race engine operating under high load and high RPM conditions needs high amounts of anti-wear additives (Zinc and Moly) to create a sacrificial additive coating that prevents metal to metal contact in your engine.
Modern Engine Set-up:
Decreased anti-wear (i.e. Zinc)
and more detergents: Read more »