What octane gas do you use? (The Mother thread)
01-12-12, 12:53 PM
#151
It's probably fine to run regular if you never run your car past 1/2 throttle. If the cars volumetric effeciency isn't very high there will be less cylinder pressure before ignition. Pressure and temperature are what cause detonation.
I still think it's a bad move, and would never recommend it.
I still think it's a bad move, and would never recommend it.
01-13-12, 04:18 PM
#156
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here is a link to a good article explaining octane. a hydrocarbon unit is a carbon atom with one hydrogen atom to the top, and one to the bottom. the chains they refer to are hydrocarbon units connected side to side. if eight of them (the carbon atoms) are coinnected side to side that is an octane. the energy released does not depend on whether you are exploding octanes, heptanes, or any other "tanes. all gasoline has several different 'tanes in it. its just that the higher the octane, the more of the longer chains it has. this reduces volatility and means you can compress it more (which raises the temperature) before it self-detonates without a spark. it is the explosion in a smaller space that leads to greater power being supplied to the drivetrain, not the inherent qualities of the gasoline.
http://auto.howstuffworks.com/fuel-e...uestion901.htm
there was also a show on this that might have been in the "modern marvels" series, but i'm not sure of that.
at higher altitudes, the thin air effectively raises your octane rating by 2-3 points. i'm in denver. i burn regular (listed as 85 octane) and never have knocking even when driving up through the mountains up to 143,000 feet. both before and after the switch to regular i got right around 19.5 mpg overall. i live in the burbs and don't do a lot of true "city" stop and go driving.
http://auto.howstuffworks.com/fuel-e...uestion901.htm
there was also a show on this that might have been in the "modern marvels" series, but i'm not sure of that.
at higher altitudes, the thin air effectively raises your octane rating by 2-3 points. i'm in denver. i burn regular (listed as 85 octane) and never have knocking even when driving up through the mountains up to 143,000 feet. both before and after the switch to regular i got right around 19.5 mpg overall. i live in the burbs and don't do a lot of true "city" stop and go driving.
02-13-12, 11:42 AM
#158
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I use 89 all the time and it runs great. I should try the 87 but haven't yet. If you don't get preignition and see no loss of power you will be fine. Try 5 gallons the first time.
02-13-12, 04:28 PM
#160
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In my LS, I use 91 octane.
Mike
02-13-12, 04:53 PM
#161
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I use the best fuel I can which around here is 91 octane from Chevron. All of our fuel has 10% ethanol in it.
Stan
02-13-12, 07:21 PM
#163
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If the car's manual says premium i give the car premium, every other car gets 87 lucky in NY we have 93, if a car is stock there's no reason to use more than what's needed, it's funny when guys throw 93 octane in a civic and expect to hit anything faster than the usual 18's in a qtr
