R 4SR+ racing gasoline is formulated from low sensitivity high octane leaded blend stocks, chemically stable oxygenates and selected refinery streams. These make the 4SR+ very stable and resistant to detonation within the MSA Blue book specification for leaded fuels. It is a legal fuel for those series who have sought sanction to use low lead fuels.
Suitable for compression ratios up to 11:1. Meets BS4040.