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Is 87 good enough?

BritishGuy

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I run 93 because I knock like crazy on 87 - sounds like a diesel engine when slowly accelerating or going up a parking garage ramp .

I'm certainly glad gas prices are coming down right now, though. :P
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BritishGuy

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Yes, I've got the 3.6 with the manual.

My local stealership heard the sound and didn't know what it was - the lead tech rode with me for ~10 miles. He said he doesn't want to start pulling stuff apart to troubleshoot it and told me that since I have a long warranty, I should just come back when it gets worse or blows up.

I come from being very familiar with turbo vehicles and heavily tuning them. The last two I had, GTI and Mazdaspeed3, were both running a full stage 2 setup and at some point had both off-the-shelf or custom tunes and none of them ever had any knock.
 

Jmonroe

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Alcohol always reduces mpg. If you could find 87 with no alcohol you'd likely get similar results. Unfortunately thats difficult to find outside an airport.
 

OldGuyNewJeep

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I grabbed the ethanol free and went about my business
Apples and oranges, then. Rerun your test with the same ethanol content and I promise you won’t get the same dramatic result.

Also, eff Connecticut and their 10% Ethanol. My (older) boat hates that crap, but ethanol free gas can only be gotten at small airports and race shops... and its $$$$. I envy you guys who can buy it at the regular pump.
 

OldGuyNewJeep

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Are you sure you're getting 87 octane ethanol free at an airport, and not 100 low lead? I've been out tinkering around the airport before and seen cars come in and fill up from the pump which is labeled as 100LL, typically high school to 20-somethings with racey looking hatchbacks, and I've always wondered if they knew what they were doing or not. I am certainly no expert but I was under the impression that most small aircraft call for 100LL. In fact I only know of one airport near Denver that offers mogas, that's KLMO in Longmont, and I'm not even sure if that is ethanol free.
I’ve never tried buying it, myself, so you may be right.
 

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blnewt

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In our 09 Infiniti G37 I get almost a 10% reduction in mpg running 10% crapenol, vs crapenol-free. It's such junk! Our best mpg was 31, and only 27.5 w/ the junk :( And this was the same road trip, same time of year.
 

Jmonroe

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Are you sure you're getting 87 octane ethanol free at an airport, and not 100 low lead? I've been out tinkering around the airport before and seen cars come in and fill up from the pump which is labeled as 100LL, typically high school to 20-somethings with racey looking hatchbacks, and I've always wondered if they knew what they were doing or not. I am certainly no expert but I was under the impression that most small aircraft call for 100LL. In fact I only know of one airport near Denver that offers mogas, that's KLMO in Longmont, and I'm not even sure if that is ethanol free.
It's been almost 30 years since I've had a reason to hang out at an airport, since I sold the last airplane I owned.

Both my airplanes were antiques, even back then, and both used 87, available at the airport at the time. You could confirm which you were pumping by the color. Dyes were used to tint the fuel for just this purpose. Without checking to confirm I think the 87 was tinted red, the 100 blue/green. Our club aircraft used 100LL.

While I was actively flying the EAA and others were lobbying heavily to make auto gas legal under specific circumstances which would have included many antiques or home builts and they were successful. Not sure how widely available it ever became at airports, however. It would probably depend on the local clientele. A small airport utilized by antique/classic/older aircraft perhaps.
 

RoadiJeff

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If you have a 2.0 use 91 for optimal performance, as is recommended in your owner's manual.
 
 







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