We talked with Technical Operations Manager Mike Miller about the latest release from Sunoco Racing Fuels. It’s a highly oxygenated fuel that they are calling EXO2. Miller says, “This fuel can be used in any application but the daily street driver. Not that you couldn’t, it’s just not legal.”
Miller explained that the EXO2 fuel works great in crate, two barrel, and iron head engines or engines running at higher elevations.
The higher oxygen content requires a richer air/fuel mixture to get the biggest bang in your combustion cylinder. Running EXO2 without the proper air/fuel mixture will lean out the engine, and as we all know, a lean motor is a very unhappy motor. Sunoco recommends a stoichiometric air/fuel ratio of 10 to 15 % over what you currently run.
So how much is highly oxygenated? Miller told us that the EXO2 has about three times the oxygen weight percentage of street fuel. That’s right, three times the weight percentage.
Rated at 107 octane, the racing fuel has no MtBE oxygenates but does contain lead. So if you’re thinking about adding a catalytic converter to your race car, this fuel might not be for you.
Miller told us that the EXO2 fuel should have a shelf life of two years when properly stored. It’s highly unlikely that anyone would keep this fuel on the shelf that long.
For more information on the new EXO2 racing fuel from Sunoco, visit them at www.sunocoinc.com.