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I run 88-89 all the time, especially lately. Altitude does play a role, as here in Utah as well as most Rocky Mountain states, regular unleaded 85, mid-grade 88, and premium 91. A few chains have four grades, 85, 87, 89, and 91...😎
Yeah, because blown engines already adjust to air density, it seems that running 85 octane even at elevation would not be a great idea (for an engine that runs on regular 87).
 

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Yeah, because blown engines already adjust to air density, it seems that running 85 octane even at elevation would not be a great idea (for an engine that runs on regular 87).
Well supposedly at elevation above 5000', it's like adding 2 octane points, but like you said, the car is constantly adjusting the fuel mixture, and I think air density would be one of those, but who knows. Mine runs fine on 88, and we're right around 5400' here in my town. Salt Lake City is a little lower at around 4300'...😎
 

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Well supposedly at elevation above 5000', it's like adding 2 octane points, but like you said, the car is constantly adjusting the fuel mixture, and I think air density would be one of those, but who knows. Mine runs fine on 88, and we're right around 5400' here in my town. Salt Lake City is a little lower at around 4300'...😎
Yep, you'd be fine with 87 also, no matter the altitude. Seems that even though 85 octane gas is still available in places like Denver, it should only be used in carburated engines, and to be avoided especially in turbo/supercharged engines. Turbos/superchargers create their own air pressure/density so pretty much oblivious to elevation, but fuel/air management requires that recommended octane be used. Many question why 85 gas is still being sold at all... (not to be confused with E-85 Flex fuel).
 

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Yep, you'd be fine with 87 also, no matter the altitude. Seems that even though 85 octane gas is still available in places like Denver, it should only be used in carburated engines, and to be avoided especially in turbo/supercharged engines. Turbos/superchargers create their own air pressure/density so pretty much oblivious to elevation, but fuel/air management requires that recommended octane be used. Many question why 85 gas is still being sold at all... (not to be confused with E-85 Flex fuel).
so taking into account that I live in Breckenridge for most of the year (7-8 months) and go up to the high country in the summer, does that mean I should definitely stick to the 91?

Elevation around summit county, CO is 9,000-10,000ft usually
 

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so taking into account that I live in Breckenridge for most of the year (7-8 months) and go up to the high country in the summer, does that mean I should definitely stick to the 91?

Elevation around summit county, CO is 9,000-10,000ft usually
If your intention is to run the 2.0T at its maximum performance, then 91 is what you want, 89 a close second. Forget elevation, beause you have a turbo, it doesn't matter, follow the owner's manual for octane.

That said... 91 is expensive and your engine doesn't absolutely need it. Others here with a turbo KL could tell you more about the tiny performance advantage of 91 over 87, and/or a slight MPG advantage... but you'd be fine with 87. Or even 88 (which is 15% ethanol).
 

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so taking into account that I live in Breckenridge for most of the year (7-8 months) and go up to the high country in the summer, does that mean I should definitely stick to the 91?

Elevation around summit county, CO is 9,000-10,000ft usually
88-89 is fine, I run it all the time. I do run 91 premium when I tow, and definitely if I go to the beach. @Mark_ I do think altitude still plays a factor, even on the electronically controlled turbo engines, and non turbos as well. Just don't buy crappy gas like Maverik. I think you guys have those in Colorado, it's not top tier, and has zero detergent additives...😎
 

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88-89 is fine, I run it all the time. I do run 91 premium when I tow, and definitely if I go to the beach. @Mark_ I do think altitude still plays a factor, even on the electronically controlled turbo engines, and non turbos as well. Just don't buy crappy gas like Maverik. I think you guys have those in Colorado, it's not top tier, and has zero detergent additives...😎
I think turbos definitely hold an advantage at elevation over atmospheric engines, because of air density. If I spent any significant driving time above 4-5K feet, I'd try and get a turbo for sure (or supercharger). As far as engine management goes, in modern cars at least, octane doesn't play a big role anymore, not like in the good 'ol carburator days.

Look at hill climbs like Pike's Peak, record holders all run turbos. Except... the ultimate record in a VW I.D.R full electric prototype... yeah, who cares about altitude with an electric motor ;)

I also enjoy watching vids of those crazy people on blown snowmobiles doing insane climbs up big montains.

 

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88-89 is fine, I run it all the time. I do run 91 premium when I tow, and definitely if I go to the beach. @Mark_ I do think altitude still plays a factor, even on the electronically controlled turbo engines, and non turbos as well. Just don't buy crappy gas like Maverik. I think you guys have those in Colorado, it's not top tier, and has zero detergent additives...😎
ok for sure, well I'd say 90% of the time I am hitting Costco on my way to or from the mountains, and they only offer 87 OR 91, nothing in between. so I guess I'll stick to 91 for now.

I haven't driven my car really much in the city now that I have the e-bike..... hoping to keep it that way!

I think turbos definitely hold an advantage at elevation over atmospheric engines, because of air density. If I spent any significant driving time above 4-5K feet, I'd try and get a turbo for sure (or supercharger). As far as engine management goes, in modern cars at least, octane doesn't play a big role anymore, not like in the good 'ol carburator days.

Look at hill climbs like Pike's Peak, record holders all run turbos. Except... the ultimate record in a VW I.D.R full electric prototype... yeah, who cares about altitude with an electric motor ;)

I also enjoy watching vids of those crazy people on blown snowmobiles doing insane climbs up big montains.

first of all, wtf. that is nuts. second of all, that looks like an incredible spot to shred some pow on the downhill. I wish I was riding down that on my snowboard right about now! This is what I'm riding currently.
Sky Cloud Mountain Snow Ecoregion
 

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ok for sure, well I'd say 90% of the time I am hitting Costco on my way to or from the mountains, and they only offer 87 OR 91, nothing in between. so I guess I'll stick to 91 for now.

I haven't driven my car really much in the city now that I have the e-bike..... hoping to keep it that way!



first of all, wtf. that is nuts. second of all, that looks like an incredible spot to shred some pow on the downhill. I wish I was riding down that on my snowboard right about now! This is what I'm riding currently.
View attachment 220052

😁 😁 (and no, I wasn't there ;) )
 

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Finally got my light installed behind the grill.
I'll have to check it against a wall at some point, but it may be hitting higher than I initially wanted.
I used a Mohawk bracket and this light.
AmazonSmile: Auxbeam 12 Inch 300W LED Light Bar Amber White Strobe LED Light Pod Offroad Driving Light Spot LED Work Light Pod Lights with Wiring Harness for Trucks Car Pickup ATV Jeep Boat Golf Cart (SIX Modes) : Automotive
Definitely avoid high aim with those. Aiming against a wall won't show you real aim, best to do it on a quiet road, at night, so you can throw far enough to know what's going on.
 

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Definitely avoid high aim with those. Aiming against a wall won't show you real aim, best to do it on a quiet road, at night, so you can throw far enough to know what's going on.
Yea, I had wanted it for amber fogs mostly, but I'm at the lowest adjustment, so it may end up not being able to use on the road at all.
 

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Finally got my light installed behind the grill.
I'll have to check it against a wall at some point, but it may be hitting higher than I initially wanted.
I used a Mohawk bracket and this light.
AmazonSmile: Auxbeam 12 Inch 300W LED Light Bar Amber White Strobe LED Light Pod Offroad Driving Light Spot LED Work Light Pod Lights with Wiring Harness for Trucks Car Pickup ATV Jeep Boat Golf Cart (SIX Modes) : Automotive

View attachment 220210

View attachment 220211
nice I like that placement. Can you take some more pics?
 

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Yea, I had wanted it for amber fogs mostly, but I'm at the lowest adjustment, so it may end up not being able to use on the road at all.
Hmmm. Well, there must be a way, if the lowest adjustment is too high. Shims maybe ? Or maybe it's the optics, not producing a cutoff to protect from throwing glare. Any fog light design must provide a sharp cutoff, to keep the light low...
 
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