e85fuel
Differences
This shows you the differences between two versions of the page.
|
e85fuel [2009/02/16 08:21] twdorris |
e85fuel [2024/03/15 11:16] |
||
|---|---|---|---|
| Line 1: | Line 1: | ||
| - | ====== Running E85 (or E70 or Exx) ====== | ||
| - | When running a mix of ethanol and gasoline, you have to account for the difference in fuel makeup when calculating your global fuel adjustment. Some common numbers you'll need for this are provided below. | ||
| - | |||
| - | ^ Fuel ^ Stoich AFR ^ Gas ratio ^ | ||
| - | |Gas | 14.7| 1.00| | ||
| - | |E70 | 10.6975| 0.7287| | ||
| - | |E85 | 9.8526| 0.670| | ||
| - | |E100 | 9.0078| 0.613| | ||
| - | |||
| - | To calculate these values, use the following formula: | ||
| - | |||
| - | <% ethanol> * 9.0078 + <% gasoline> * 14.64 | ||
| - | |||
| - | For example, for running pure E85, you would use: | ||
| - | |||
| - | 0.85 * 9.0078 + 0.15 * 14.64 = 9.8526 | ||
| - | |||
| - | The 14.64 figure above comes from the chemically correct stoichiometric ratio of gasoline. A lot more data can be found on the [[http://en.wikipedia.org/wiki/E85_in_standard_engines|wikipedia E85 page]]. | ||
| - | |||
| - | |||
| - | ===== Global fuel ===== | ||
| - | You have to account for the difference listed above when calculating global fuel for a car running ethanol-based fuel. The simplest way to do this, IMO, is to first calculate a "corrected" injector size and then use the normal global fuel calculations everyone else uses. | ||
| - | |||
| - | For example, if you're running 100% E85 with 850 cc/min injectors, your injectors are flowing the equivalent of 570 cc/min injectors on gasoline: | ||
| - | |||
| - | 850 * 0.670 = 570 | ||
| - | |||
| - | The 0.670 figure comes from the gas ratio column of the table above. | ||
| - | |||
| - | So now you can calculate your new global fuel using the standard formulas and 570 cc/min injector size instead of 850. | ||
| - | |||
| - | 450 / 570 - 1 = -21% | ||
| - | |||
| - | |||
e85fuel.txt ยท Last modified: 2024/03/15 11:16 (external edit)
Page Tools
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Share Alike 4.0 International
