Royal Purple HPS street motor oils offer several reasons and advantages to maximize performance in your gas or diesel engine. How about reduced heat, friction and wear on your engine? Or, improved fuel economy, lower emissions and longer engine component life? High performance street oils can even help on mornings when you've got to cold start your engine! Royal Purple HPS is fortified with advanced additive technology - zinc/phosphorus anti-wear additives and Synerlec - to surpass many other oils. Increased pressure is met with increased viscosity to meet the demands of your modified engine with a higher level of performance and protection.