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Eric Coffey Eric Coffey is offline
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Join Date: Nov 2000
Location: AZ
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Quote:
Originally Posted by masraum View Post
The CR is 10.5:1.
That is certainly high enough that you should realize power and MPG benefits with higher-octane fuel. Of course, it depends on the specific vehicle's ECU mapping/sensors to take advantage of it. Id imagine a newer Subaru would be able to go a bit more aggressive on the timing to give you a slight boost. The HP may not be noticeable, but if you carefully track your mileage over several tanks, I'd be surprised if you didn't realize a couple more MPGs with 91+ over 87 (again, non-ethanol). As a bonus, the higher-test stuff should cause less oil dilution, and has a higher concentration of add-pack (detergents) as well. Though, I usually run a bottle Techron towards the end of oil change intervals anyway.
Quote:
Originally Posted by masraum View Post
I didn't notice an ethanol free 87, but I'll check the next time that I'm there. That's what I'll use if it's available. If not, then I'll just stick with regular 87.
Yeah, if you don't want to bother with the higher-octanes, I'd still try to avoid E10 87 whenever possible.
Old 12-15-2020, 02:31 PM
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