We recommend VP NO2 race fuel for fogger or three-stage nitrous oxide applications with CRs up to 18:1. It bridges the gap between VP’s C16 and C23. VP NO2 has both higher octane and lower specific gravity than most nitrous fuels. As a result, it may require enriching the fuel mixture more than would be required for C16. Be sure to check out VP's line of exceptional racing lubricants. They provide outstanding durability and deliver unmatched wear protection under extreme conditions for vital components.