Red Line Oils allow 1 to 3% more horsepower output than petroleum oils of similar viscosity while providing much more protection. Red Line racing oils also feature more ZDDP than street oils for increased protection of solid lifters and flat tappets. Even though these racing oils are formulated as straight grades, their inherent multigrade behavior provides low temperature properties that are similar to petroleum-based multigrade oils, but without the unstable polymer thickeners. To reduce the chance of detonation, these racing oils contain very low amounts of detergent and are therefore not recommended for street use.
Viscosity equivalents and recommendations: