Originally Posted by wdn
The Top Tier spec says that the gasoline must contain at least 8% ethanol but no more that 10%. If a Costco station is selling 15% ethanol then it is no longer Top Tier. Either that or the definition of Top Tier has changed.
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Quote
4.3.1.2 Base Fuel. The base fuel shall conform to ASTM D 4814 and shall contain commercial fuel grade ethanol conforming to ASTM D 4806. All gasoline blend stocks used to formulate the base fuel shall be representative of normal territory refinery operations and shall be derived from conversion units downstream of distillation. Butanes and pentanes are allowed for vapor pressure adjustment. The use of chemical streams is prohibited. The base fuel shall have the following specific properties after the addition of ethanol:
1. Contain enough denatured ethanol such that the ethanol content is no less than 8.0 and no more than 10.0 volume percent as measured by ASTM D 4815 or D 5845. In markets with lower fuel ethanol content, fuel matching the market conditions of fuel ethanol content can be used upon approval.
2. Contain no less than 8 volume percent olefins as measured by ASTM D 1319 or D 6729.
3. Contain no less than 28 volume percent aromatics as measured by ASTM D 1319 or D 6729.
4. Contain no more than 80 mg/kg sulfur as measured by ASTM D 2622 or D 5453.
5. Produce a 90% evaporated distillation temperature no less than 290°F as measured by ASTM D86.
6. Produce IVD no less than 500 mg averaged over all intake valves.
7. A Certificate of Analysis showing both the detailed test fuel composition results and source should accompany the additive results package. This certificate should also contain the unwashed and washed gum level of the base fuel according to ASTM D381.
The Top Tier spec says that the gasoline must contain at least 8% ethanol but no more that 10%. If a Costco station is selling 15% ethanol then it is no longer Top Tier. Either that or the definition of Top Tier has changed.
Got a link for this?
Never mind. Found the answer.
Quote
4.3.1.2 Base Fuel. The base fuel shall conform to ASTM D 4814 and shall contain commercial fuel grade ethanol conforming to ASTM D 4806. All gasoline blend stocks used to formulate the base fuel shall be representative of normal territory refinery operations and shall be derived from conversion units downstream of distillation. Butanes and pentanes are allowed for vapor pressure adjustment. The use of chemical streams is prohibited. The base fuel shall have the following specific properties after the addition of ethanol:
1. Contain enough denatured ethanol such that the ethanol content is no less than 8.0 and no more than 10.0 volume percent as measured by ASTM D 4815 or D 5845. In markets with lower fuel ethanol content, fuel matching the market conditions of fuel ethanol content can be used upon approval.
2. Contain no less than 8 volume percent olefins as measured by ASTM D 1319 or D 6729.
3. Contain no less than 28 volume percent aromatics as measured by ASTM D 1319 or D 6729.
4. Contain no more than 80 mg/kg sulfur as measured by ASTM D 2622 or D 5453.
5. Produce a 90% evaporated distillation temperature no less than 290°F as measured by ASTM D86.
6. Produce IVD no less than 500 mg averaged over all intake valves.
7. A Certificate of Analysis showing both the detailed test fuel composition results and source should accompany the additive results package. This certificate should also contain the unwashed and washed gum level of the base fuel according to ASTM D381.
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