AMSOIL DOMINATOR® 5W-20 100% SYNTHETIC RACING OIL

AMSOIL DOMINATOR 5W-20 100% Synthetic Racing Oil delivers straight-grade protection in a multi-grade formula, built specifically for high-performance racing engines running SAE 20 weight oil. It is heavily fortified with zinc and phosphorus anti-wear additives and formulated with a proprietary friction modifier to maximize horsepower while keeping critical engine surfaces protected under extreme conditions.

Racing engines live at the edge. Sustained high RPM, extreme cylinder pressures, and shock loading from aggressive throttle inputs push lubricants far beyond what conventional or even standard synthetic oils are designed to handle. A 5W-20 racing application compounds that challenge because thinner oils must maintain film strength and resist viscosity loss under brutal mechanical shear, or protection disappears when it matters most.

RESISTS VISCOSITY LOSS UNDER MECHANICAL SHEAR
Thinner racing oils are vulnerable to shear-induced viscosity breakdown, especially in modified small-block and bracket racing engines that sustain high RPM for extended periods. DOMINATOR 5W-20 is engineered with a shear-stable synthetic base that resists thinning under mechanical stress, maintaining its protective oil film throughout the race. Its high-temperature/high-shear viscosity measures 3.1 cP at 150°C per ASTM D5481, confirming that the oil holds its film strength when heat and shear forces are at their peak.

FORTIFIED WITH ZINC AND PHOSPHORUS FOR EXTREME WEAR PROTECTION
Flat-tappet cams, high-tension valve springs, and tight bearing clearances in race-prepped engines demand anti-wear chemistry that goes well beyond what emissions-compliant passenger car oils can offer. DOMINATOR 5W-20 is loaded with zinc and phosphorus (ZDDP) anti-wear additives to protect against scuffing and metal-to-metal contact in severe racing conditions. In Four-Ball Wear testing per ASTM D4172 at 40 kg, 150°C, and 1800 rpm for one hour, DOMINATOR 5W-20 produced a wear scar of just 0.40 mm.

PROPRIETARY FRICTION MODIFIER MAXIMIZES HORSEPOWER
Every fraction of a horsepower counts in competitive racing. DOMINATOR 5W-20 is formulated with a proprietary friction modifier that reduces parasitic energy loss within the engine, translating directly to more power at the wheels and cooler engine operating temperatures. Lower friction means less heat generated internally, which promotes longer component life and more consistent lap times across a full race distance.

EXCELLENT COLD-FLOW AND STARTUP PROTECTION
A pour point of -48°C (-54°F) per ASTM D97 makes DOMINATOR 5W-20 the lowest-pour-point oil in the entire DOMINATOR lineup. This matters during cold engine startups and pre-race warm-up cycles where oil needs to reach critical surfaces quickly. Less drag during warm-up also means the engine comes up to operating temperature more efficiently, reducing the window of vulnerability before full oil pressure and film strength are established. Cold-cranking simulator viscosity measures 5,347 cP at -30°C per ASTM D5293.

THERMALLY STABLE AT EXTREME OPERATING TEMPERATURES
Racing engines routinely operate at temperatures that would degrade lesser oils in minutes. DOMINATOR 5W-20 uses a thermally stable synthetic base chemistry that resists oxidation and thermal breakdown under sustained high heat. Its flash point of 230°C (446°F) and fire point of 254°C (489°F) per ASTM D92 reflect a base oil that holds together when the heat is relentless. A Total Base Number of 8.0 provides acid-neutralizing capacity to handle combustion byproducts generated under aggressive fueling strategies.

SPECIFICATIONS AND COMPATIBILITY
DOMINATOR 5W-20 is compatible with leaded and unleaded gasoline, diesel, alcohol, nitromethane, and nitrous oxide. It is designed for domestic and import high-performance racing engines where an SAE 20 viscosity oil is suitable, including modified small-block engines, bracket racing, asphalt late model, and midget applications. This is a racing-only formulation. It is not intended for long-term use in passenger cars or light trucks.

SERVICE LIFE
DOMINATOR is formulated for racing duty cycles. The vehicle owner is responsible for determining an appropriate oil service interval based on the event, application, and viscosity needs. Oil analysis through Oil Analyzers Inc. (a division of AMSOIL) is available for racers who want data-driven insight into oil condition and engine wear trends between events.