Fuel Finder

E85-R

Sunoco E85-R is an unleaded racing fuel containing 85 volume % ethanol. It can only be used in fuel systems designed specifically for E85 blends. Because it is highly oxygenated and requires increased fuel flow compared to conventional non-oxygenated fuels, consult with your fuel injection system or carburetor supplier for correct air/fuel ratio calibrations.

Sunoco E85-R is blended to consistently contain 85% ethanol. Conventional E85 can vary from about 51% to 83% ethanol or so but rarely contains 85% ethanol. Conventional E85 can also vary seasonally; the composition of Sunoco E85-R race fuel does not change. The non-ethanol portion of Sunoco E85-R is comprised of highly-refined race fuel hydrocarbons for stability and consistency. Sunoco E85-R is the racer’s fuel of choice where E85 fuels are allowed.

Sunoco E85-R does not contain metallic additives and will not harm oxygen sensors. It should be stored in dark, tightly sealed containers where the temperature is stable. Handled under such conditions, shelf life is in excess of 1 year. Check with your fuel system and fuel container manufacturers for compatibility with ethanol and E85 blends. Please note that due to the high oxygenation of E85-R, the octane values are estimated.

Note: the octane ratings for E85-R are estimates. The conventional ASTM laboratory octane tests cannot accommodate the high oxygen content of fuels like E85-R.

Technical Details

  • Color
    Pale Green
  • Octane (R+M)/2
    99
  • Research Octane
    104
  • Motor Octane
    94
  • Specific Gravity
    0.79
  • Weight (lbs/gallon)
    6.6
  • Reid Vapor Pressure (PSI)
    4.2
  • 10% Evaporation (°F)
    166
  • 50% Evaporation (°F)
    169
  • 90% Evaporation (°F)
    171
  • Stoichiometric Air/Fuel Ratio
    9.8
  • Oxygen (weight%)
    30
  • Ethanol (volume%)
    85
  • H/C Ratio
    2.7
  • O/C Ratio
    0.39
  • Lower Heating Value (Btu/Gallon)
    82200
  • Lower Heating Value (Btu/Pound)
    12500
  • Leaded
    No

Applications:

  • Road Course
  • Asphalt Oval
  • Dirt Oval
  • Off-road
  • Rally
  • Drag
  • Truck and Tractor Pulling
  • Miscellaneous Nitrous, Superchargers, Turbochargers

Sanctioning Bodies

  • IndyCar

Tech Corner

Specific Gravity – What Is It And Why Does It Matter?

Specific Gravity Definition: specific gravity (noun) - the ratio of the...

Race Fuel Storage

Race fuels generally last longer than typical pump gas but often times race...

Beyond Octane

Overheard at the local track: “High octane fuels burn slower.” “My...