May 29, 20214 yr I was up at Zion, and noticed that "regular" gas there is 85 octane, and "mid-grade" is 87. High was 90. Somebody said that at high altitudes, lower octane works fine, but I used the 87 anyway (which is "regular" in CA. What's the story?
May 29, 20214 yr I don’t know the story but I drove around WY for 6 years on 85 octane with no issues.
May 29, 20214 yr Cars that require high octane have high compression engines. If you use 87 in a car that requires 93 you run the risk of pre-ignition (might burn hole in piston). I don't know for certain but I think since the air is less dense (less o2) 90 octane at 6,000' is the same as 93 at sea level.The car's knock sensor listens for engine ping, and will retard the timing if any it's detected.Sent from my Pixel 4 using Tapatalk
May 29, 20214 yr 2 hours ago, iamthepush said: you run the risk of pre-ignition (might burn hole in piston). Well, we've all been there, right? ... Right?
May 30, 20214 yr Most cars now have turbos or superchargers. If you have any forced induction it doesn't make a shit at all.
May 30, 20214 yr Most cars now have turbos or superchargers. If you have any forced induction it doesn't make a shit at all.Are you retardation? A- most cars today are naturally aspirated2-If you have a supercharger or turbocharger you have a high compression engine.God, you're dumbSent from my Pixel 4 using Tapatalk
May 30, 20214 yr https://cars.usnews.com/cars-trucks/cheapest-turbocharged-cars Super weird. It's almost like anyone who wants good fuel economy has FI. Ecoboost from Ford. Eco from any vendor. Most Subaru have a small turbo. Its weird how stupid you are even the damned Chevy sonic has a turbo. This isn't 2010, you are the stupid one. Its not for performance anymore its for fuel economy. Shut the fuck up about things you don't know about and save yourself some embarrassment next time.
May 30, 20214 yr https://cars.usnews.com/cars-trucks/cheapest-turbocharged-cars Super weird. It's almost like anyone who wants good fuel economy has FI. Ecoboost from Ford. Eco from any vendor. Most Subaru have a small turbo. Its weird how stupid you are even the damned Chevy sonic has a turbo. This isn't 2010, you are the stupid one. Its not for performance anymore its for fuel economy. Shut the fuck up about things you don't know about and save yourself some embarrassment next time. Does it hurt being so dumb? Most cars on the road are N/A. Sure MAYBE 51% of 2021 models might have a turbo/S/c, And where the fuck have you been? When the Chevy Sonic came out in 2012 you could get a 1.4 turbo.Sent from my Pixel 4 using Tapatalk
May 30, 20214 yr 35 minutes ago, immamac said: https://cars.usnews.com/cars-trucks/cheapest-turbocharged-cars Super weird. It's almost like anyone who wants good fuel economy has FI. Ecoboost from Ford. Eco from any vendor. Most Subaru have a small turbo. Its weird how stupid you are even the damned Chevy sonic has a turbo. This isn't 2010, you are the stupid one. Its not for performance anymore its for fuel economy. Shut the fuck up about things you don't know about and save yourself some embarrassment next time. I thing politics in the DT is really starting to wear on Immamac.
May 30, 20214 yr 34% in 2020. Hardly "most" and hardly a mistake that deserves recrimination. Sheath your swords, Gentlemen. https://www.energy.gov/eere/vehicles/articles/fotw-1137-june-8-2020-one-third-all-light-duty-vehicles-produced-2019-model
May 30, 20214 yr 2 hours ago, immamac said: Most cars now have turbos or superchargers. If you have any forced induction it doesn't make a shit at all. What do you mean by “it doesn’t make a shit at all”? You mean that the fuel octane doesn’t matter with forced induction engines?
May 30, 20214 yr On 5/29/2021 at 2:44 PM, iamthepush said: Cars that require high octane have high compression engines. If you use 87 in a car that requires 93 you run the risk of pre-ignition (might burn hole in piston). I don't know for certain but I think since the air is less dense (less o2) 90 octane at 6,000' is the same as 93 at sea level. The car's knock sensor listens for engine ping, and will retard the timing if any it's detected. Sent from my Pixel 4 using Tapatalk 23 hours ago, Parliament said: Thinner air -> less O2 -> low octane OK We just bought a 2006 Volvo that has an inline 5 engine with turbo. Takes the high octane gas. But we live at ~5,000 ft elevation, so y'all are telling me I could be putting the mid-grade in it?
May 31, 20214 yr 2 hours ago, High Plains Drifter said: We just bought a 2006 Volvo that has an inline 5 engine with turbo. Takes the high octane gas. But we live at ~5,000 ft elevation, so y'all are telling me I could be putting the mid-grade in it? I wouldn't. It's asking for trouble. Two things make an engine susceptible to detonation or knocking, high compression ratio (>9.0) and forced induction. They often go together, but don't have to. Both raise the energy state of the fuel-air mixture in a combustion chamber to a level where it is more likely to to explode before ignition. Knock sensors seemed to be pretty effective at reducing/eliminating knock in high-compression engines, so you were safe with a non-turbo using lower octane gas with some performance or mileage hit. That doesn't seem to be reliably true with turbocharged engines. A goodly number of turbo engines have detonation-related failures and it's often traced to using lower octane fuel. Synthetic oil seems to have some positive effect on reducing detonation, also, apparently because they outgas fewer volatile fractions or molecules that can contribute to detonation. Finally, air is less dense at altitude because of lower atmospheric pressure. A turbocharger or supercharger exists to raise the air pressure above atmospheric (they were essentially invented to make piston engines run well at altitude on aircraft), so the notion that there isn't enough O2 to cause detonation at altitude is suspect. Small addendum. It looks like lower octanes are or were standard at high altitudes because high octane fuels can actually make an engine hard to start at high altitudes and were satisfactory running in the lower-O2 environment. I'm not sure that latter part holds completely true anymore with more modern engines. Edited May 31, 20214 yr by TwiceHorn
May 31, 20214 yr One thing I've learned over a decade of reading message boards. Don't get advice on octane from a message board.
May 31, 20214 yr 2 hours ago, High Plains Drifter said: We just bought a 2006 Volvo that has an inline 5 engine with turbo. Takes the high octane gas. But we live at ~5,000 ft elevation, so y'all are telling me I could be putting the mid-grade in it? Use whatever the owners manual says. Don't make this a thing.
May 31, 20214 yr , so y'all are telling me I could be putting the mid-grade in it? If you want the privilege of maybe having to buy a new engine.Curious, what part of my post led you to believe that you could put mid grade in it? What octane is mid in your area?Sent from my Pixel 4 using Tapatalk
May 31, 20214 yr 15 hours ago, iamthepush said: Curious, what part of my post led you to believe that you could put mid grade in it? What octane is mid in your area? On 5/29/2021 at 2:44 PM, iamthepush said: I don't know for certain but I think since the air is less dense (less o2) 90 octane at 6,000' is the same as 93 at sea level.
May 31, 20214 yr Author I wonder how many high-end rental cars/loaner cars get filled up with Premium as specified.
June 1, 20214 yr 21 hours ago, Pato del Muerto said: Next can we discuss carb kits for small engines at high altitude? The higher the altitude the smaller the jet. http://cdn.powerequipment.honda.com/pe/pdf/pubs/pci54675.pdf
June 2, 20214 yr We stopped at the same gas station in Raton, NM to get the timing adjusted on my grandpa’s motorhome every time we went skiing when I was a kid. One year he got a new motorhome and we didn’t have to stop anymore. Thought that might be relevant.
June 2, 20214 yr On 5/31/2021 at 1:01 PM, Gil Bang said: I wonder how many high-end rental cars/loaner cars get filled up with Premium as specified. 12%. So "most" in Surly Mod Math.
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