Description Reviews Royal Purple’s XPR (Extreme Performance Racing) is specifically formulated for the demands of multi-platform racing environments. XPR is popular in a variety of motorsports including: NASCAR, NHRA, World of Outlaws and Bonneville Salt Flats. XPR combines the highest quality of synthetic base oil with Royal Purple’s proprietary Synerlec additive technology. Combined with additional performance enhancers to create a lubricant that maximizes horsepower and torque, while providing the highest level of protection against heat and wear. XPR provides more protection than leading synthetics and conventional lubricants including those combined with aftermarket additives. XPR's high film strength make it exceptionally well-suited for today's high performance cars and trucks, particularly turbo and supercharged engines and/or engines using nitrous. Professional engine builders and race teams cite increased horsepower and longer engine life with the use of Royal Purple. That gain is its performance advantages from Royal Purple’s proprietary Synerlec additive technology. Note: Sold as a quart bottle. Most cars need 5 to complete an oil service. Don't forget a new quality filter: Gen1, Gen2, or Gen 3!