Why no 93 octane gasoline out west?
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tar_snake (08-14-2017)
#12
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tar_snake (08-14-2017)
#13
I have used E10 87 octane since my first H-D in 06. Since then I have had every version of the twin cam including the 120's. All have run perfect on E10 87 (85 in the mountains)
Unless you have a built engine the stock HD runs regular with ease.
I manage to get 50 mpg out of them with the regular gas. Why waste money?
Unless you have a built engine the stock HD runs regular with ease.
I manage to get 50 mpg out of them with the regular gas. Why waste money?
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user 7172984932 (08-21-2017)
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#18
An engine's octane level to prevent pinging depends on its dynamic compression ratio. As elevation increases, air pressure is lower and so less air gets into the cylinders. That lowers the dynamic CR. So, less octane is needed to prevent pinging. Since less air is entering, the injection system will lower the amount of fuel as well to maintain the AFR. So the engine will produce less power. Increasing the octane will not have any affect on that. Note that if your MAP sensor is not working properly you'll likely have some problems.
#20
Since I asked the question, it seems many have jumped to the conclusion that I'm worried about not finding high octane fuel out west. That's absolutely untrue. I've used 87 octane several times above 6000 feet (fully loaded) with no discernible difference in performance. I was just curious, and wondered if anyone knew the reason.
If the altitude of the western states is the reason for only finding 89 or less octane, it would stand to reason that cities near sea level, such as Seattle, Olympia, Seaside, San Francisco, Long Beach, Santa Barbara, etc., would have the higher octane fuel available again. Is that true? I haven't been further west that central Washington. Also, we normally have 91 & 93 octane available everywhere at 700' MSL in my local area.
If the altitude of the western states is the reason for only finding 89 or less octane, it would stand to reason that cities near sea level, such as Seattle, Olympia, Seaside, San Francisco, Long Beach, Santa Barbara, etc., would have the higher octane fuel available again. Is that true? I haven't been further west that central Washington. Also, we normally have 91 & 93 octane available everywhere at 700' MSL in my local area.