(a) This section specifies test fuel properties for gasoline with ethanol (low-level blend only) and for gasoline without ethanol. Note that the “fuel type” for the fuels specified in paragraphs (b) and (c) of this section is considered to be gasoline. In contrast, fuels with higher ethanol concentrations, such as fuel containing 82 percent ethanol, are considered to be ethanol fuels rather than gasoline. We specify some test fuel parameters that apply uniquely for low-temperature testing and for testing at altitudes above 1,219 m. For all other testing, use the test fuel parameters specified for general testing. Unless the standard-setting part specifies otherwise, use the fuel specified in paragraph (c) of this section for general testing.

(b) The following specifications apply for a blended gasoline test fuel that has nominally 10% ethanol (commonly called E10 test fuel):

(1) Prepare the blended test fuel from typical refinery gasoline blending components. You may not use pure compounds, except as follows:

(i) You may use neat ethanol as a blendstock.

(ii) You may adjust the test fuel's vapor pressure by adding butane.

(iii) You may adjust the test fuel's benzene content by adding benzene.

(iv) You may adjust the test fuel's sulfur content by adding sulfur compounds that are representative of those found with in-use fuels.

(2) Table 1 of this section identifies limit values consistent with the units in the reference procedure for each fuel property. These values are generally specified in international units. Values presented in parentheses are for information only. Table 1 follows:

Table 1 of §1065.710—Test Fuel Specifications for a Low-Level Ethanol-Gasoline Blend

Open Table
Property Unit Specification Reference
procedure1
General testing Low-temperature testing High altitude testing
Antiknock Index (R + M)/2 87.0—88.42 87.0 Minimum ASTM D2699 and D2700.
Sensitivity (R-M) 7.5 Minimum ASTM D2699 and D2700.
Dry Vapor Pressure Equivalent (DVPE)3 4 kPa (psi) 60.0-63.4
(8.7-9.2)
77.2-81.4
(11.2-11.8)
52.4-55.2
(7.6-8.0)
ASTM D5191.
Distillation4
10% evaporated
°C ( °F) 49-60
(120-140)
43-54
(110-130)
49-60
(120-140)
ASTM D86.
50% evaporated °C ( °F) 88-99 (190-210).
90% evaporated °C ( °F) 157-168 (315-335).
Evaporated final boiling point °C ( °F) 193-216 (380-420).
Residue milliliter 2.0 Maximum.
Total Aromatic Hydrocarbons volume % 21.0-25.0 ASTM D5769.
C6 Aromatics (benzene) volume % 0.5-0.7.
C7 Aromatics (toluene) volume % 5.2-6.4.
C8 Aromatics volume % 5.2-6.4.
C9 Aromatics volume % 5.2-6.4.
C10 + Aromatics volume % 4.4-5.6.
Olefins5 mass % 4.0-10.0 ASTM D6550.
Ethanol blended volume % 9.6-10.0 See paragraph (b)(3) of this section.
Ethanol confirmatory6 volume % 9.4-10.2 ASTM D4815 or D5599.
Total Content of Oxygenates Other than Ethanol6 volume % 0.1 Maximum ASTM D4815 or D5599.
Sulfur mg/kg 8.0-11.0 ASTM D2622, D5453 or D7039.
Lead g/liter 0.0026 Maximum ASTM D3237.
Phosphorus g/liter 0.0013 Maximum ASTM D3231.
Copper Corrosion No. 1 Maximum ASTM D130.
Solvent-Washed Gum Content mg/100 milliliter 3.0 Maximum ASTM D381.
Oxidation Stability minute 1000 Minimum ASTM D525.

1ASTM procedures are incorporated by reference in §1065.1010. See §1065.701(d) for other allowed procedures.

2Octane specifications apply only for testing related to exhaust emissions. For engines or vehicles that require the use of premium fuel, as described in paragraph (d) of this section, the adjusted specification for antiknock index is a minimum value of 91.0; no maximum value applies. All other specifications apply for this high-octane fuel.

3Calculate dry vapor pressure equivalent, DVPE, based on the measured total vapor pressure, pT, using the following equation: DVPE (kPa) = 0.956 · pT—2.39 or DVPE (psi) = 0.956 · pT—0.347. DVPE is intended to be equivalent to Reid Vapor Pressure using a different test method.

4Parenthetical values are shown for informational purposes only.

5The reference procedure prescribes measurement of olefin concentration in mass %. Multiply this result by 0.857 and round to the first decimal place to determine the olefin concentration in volume %.

6ASTM D5599 prescribes concentration measurements for ethanol and other oxygenates in mass %. Convert results to volume % as specified in Section 14.3 of ASTM D4815.

(3) The ethanol-blended specification in Table 1 of this section is based on the volume % ethanol content of the fuel as determined during blending by the fuel supplier and as stated by the supplier at the time of fuel delivery. Use good engineering judgment to determine the volume % of ethanol based on the volume of each blendstock. We recommend using a flow-based or gravimetric procedure that has an accuracy and repeatability of ±0.1%.

(c) The specifications of this paragraph (c) apply for testing with neat gasoline. This is sometimes called indolene or E0 test fuel. Gasoline for testing must have octane values that represent commercially available fuels for the appropriate application. Test fuel specifications apply as follows:

Table 2 of §1065.710—Test Fuel Specifications for Neat (E0) Gasoline

Open Table
Property Unit Specification Reference procedure1
General testing Low-temperature
testing
Distillation Range:
Evaporated initial boiling point °C 24-352 24-36 ASTM D86
10% evaporated 49-57 37-48
50% evaporated 93-110 82-101
90% evaporated 149-163 158-174
Evaporated final boiling point Maximum, 213 Maximum, 212
Hydrocarbon composition:
Olefins volume % Maximum, 10 Maximum, 17.5 ASTM D1319
Aromatics Maximum, 35 Maximum, 30.4
Saturates Remainder Remainder
Lead g/liter Maximum, 0.013 Maximum, 0.013 ASTM D3237
Phosphorous g/liter Maximum, 0.0013 Maximum, 0.005 ASTM D3231
Total sulfur mg/kg Maximum, 80 Maximum, 80 ASTM D2622
Dry vapor pressure equivalent3 kPa (psi) 60.0-63.42 4 (8.7-9.2) 77.2-81.4 (11.2-11.8) ASTM D5191

1ASTM procedures are incorporated by reference in §1065.1010. See §1065.701(d) for other allowed procedures.

2For testing at altitudes above 1219 m, the specified initial boiling point range is (23.9 to 40.6) °C and the specified volatility range is (52.0 to 55.2) kPa ((7.5 to 8.0) psi).

3Calculate dry vapor pressure equivalent, DVPE, based on the measured total vapor pressure, pT, in kPa using the following equation: DVPE (kPa) = 0.956 · pT−2.39 or DVPE (psi) = 0.956 · pT−0.347. DVPE is intended to be equivalent to Reid Vapor Pressure using a different test method.

4For testing unrelated to evaporative emissions, the specified range is (55.2 to 63.4) kPa ((8.0 to 9.2) psi).

(d) Use the high-octane gasoline specified in paragraph (b) of this section only for engines or vehicles for which the manufacturer conditions the warranty on the use of premium gasoline.

[79 FR 23809, Apr. 28, 2014, as amended at 80 FR 9119, Feb. 19, 2015]


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