At DCI Motorsports, we take motor oil seriously. We’ve spent years using various motor oils which has led us to the following oil recommendations for engines designed before 1981.
For modern unmodified factory engines always follow the factory recommendations.
Oil for Engine break-in
The break-in oil you use is critical to the life of your newly rebuilt engine. Each brand of oil use unique formulas that they believe is optimal. From our years of experience, we have found some of these brands break down quickly and will thin early during the break-in period. From our experience we recommend Comp Camps or Lucas brand break-in oils.
Oil for normal Engine use
For normal engine use we find that Valvoline VR1 racing oil performs very well under extreme conditions. Though expensive, we also use Royal Purple racing oil. It is important to note to use “racing” oils. Though all brands have “street” oils, they typically are designed for modern engines that do not require zinc additives.
Oil weights and viscosity
An engine’s recommended oil viscosity can vary based on engine tolerances, engine parts used, and oil pump pressure and volume. The oil weight must be chosen to match your engine combination. Overly thin oils may not apply the necessary thickness of oil to critical parts, or could even escape through engine seals and gaskets, while too thick oils will starve critical parts from receiving oil and increase engine load. In either case, the wrong oil viscosity can shorten engine life.
DCI Motorsports will recommend a specific oil viscosity for your engine rebuild.
Engine oil additives
We do not recommend adding engine oil additives that claim to help with high mileage or extensive wear. If you are looking for such an oil you are better served planning an engine rebuild.
If the engine oil you use does not include high amounts of ZDDP we do recommend the use of a ZDDP additive. We recommend using Comp Cams Engine Break-In Oil Additive both during break-in and with all future oil changes when using an oil that does not have the necessary zinc additives.