Sunoco EXO2 is a very highly oxygenated race fuel. EXO2’s high oxygen content – about three times as much as pump gas – can be beneficial in crate engines, two-barrel engines, and racing classes with cylinder head limitations, as well as engines running at higher elevations.
Due to its high oxygen content, Sunoco EXO2 requires a richer air/fuel mixture. Using EXO2 without proper air/fuel mixture changes can lean out your engine. Please consult the stoichiometric air/fuel ratio data in the Technical Details section below. Since non-oxygenated race fuels typically have a stoichiometric air/fuel ratio of 14.6:1 to 15.1:1, you may need to richen your fuel mixture by 10 to 15 percent when using EXO2 depending on the fuel you are currently using.
As with any gasoline, Sunoco EXO2 should be stored in opaque, tightly sealed containers and kept where temperatures are stable. Drum pumps should be removed immediately after use. Properly stored, the shelf life of Sunoco EXO2 is one to two years.
Note: EXO2’s octane values must be estimated because of the extreme oxygenation of this fuel. The (R+M)/2 octane value of 110 is a conservative estimate.
Legal in California only for racing vehicles in sanctioned racing events.
For off-road and racing applications only.
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