6.2L Fuel Economy/Octane requirements
02-11-2011, 06:26 PM
#21
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I'm glad somebody else noticed this, hopefully the OP is still reading. While the prior two posters were correct in their statements that a vehicle tuned for regular unleaded will gain nothing from premium, they missed the fact that the L92 trucks come from the factory tuned for 91+. Because of this, the computer will pull timing if a lower octane fuel is used, and power and efficiency will suffer.
02-12-2011, 09:56 AM
#22
Thank you, sir! Likewise. I'm usually the guy with all the info and nothing to do with it, but this time it's actually relevant to me as well: I'll be picking up my 2011 Silverado 4x4 6.2 crew on Monday, after the dealer finishes getting it ready for me. Signed all the paperwork yesterday
Post up some pics when you pick 'er up!
02-12-2011, 10:04 AM
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Will do I can't wait! Plus the day I pick it up will likely be the cleanest it will ever be, since it is black and I live in the middle of the desert, and I plan on driving it like a truck. I can't wait to go out into the wilderness in my new ride.
I can't wait! Plus the day I pick it up will likely be the cleanest it will ever be, since it is black and I live in the middle of the desert, and I plan on driving it like a truck. I can't wait to go out into the wilderness in my new ride.
02-12-2011, 06:46 PM
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best ive ever managed was 20 according to the dash.. i dont know how your managing 24... calculate it and see if that thing is right....
you can def tell the power loss when you have 87 in the truck... it had 87 in it from the dealer.... so you guys buying the new ones.. make sure there putting 91-93 in it
you can def tell the power loss when you have 87 in the truck... it had 87 in it from the dealer.... so you guys buying the new ones.. make sure there putting 91-93 in it
02-14-2011, 09:06 AM
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I haven't gone on a road trip long enough to get an accurate reading. This is from driving from League City to Montgomery around 7-8 at night. Then when i got there i was showing it off to my friends. The mpgs went way down.
02-14-2011, 10:26 AM
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Octane - forgot about that part of the OP's post . . .
The 6.2s are engineered for 91+ octane fuel (and/or E85 for the '09s and newer).
Each time that the ECM detects more than approximately 6 gallons of fuel has been added to the tank, the software is written in such a way that it utilizes the high octane spark advance tables. Once a certain amount (or severity) of knock has been detected by the ECM, it then reverts to the low octane spark tables - until the next time that 6+ gallons of fuel is added to the tank.
I have NO idea what the knock "threshold" is that forces the ECM to use the low-octane spark tables, but that's how it operates.
The "low octane" spark tables WILL adversely affect your torque, power and economy!
EDIT - one more small tidbit concerning octane - some export 6.2s (bound for the middle east, IIRC) are factory tuned for 95 octane fuel, and factory rated at 443 HP!
The 6.2s are engineered for 91+ octane fuel (and/or E85 for the '09s and newer).
Each time that the ECM detects more than approximately 6 gallons of fuel has been added to the tank, the software is written in such a way that it utilizes the high octane spark advance tables. Once a certain amount (or severity) of knock has been detected by the ECM, it then reverts to the low octane spark tables - until the next time that 6+ gallons of fuel is added to the tank.
I have NO idea what the knock "threshold" is that forces the ECM to use the low-octane spark tables, but that's how it operates.
The "low octane" spark tables WILL adversely affect your torque, power and economy!
EDIT - one more small tidbit concerning octane - some export 6.2s (bound for the middle east, IIRC) are factory tuned for 95 octane fuel, and factory rated at 443 HP!
Thanks for the throughly written response Lyold, exactly what i needed to find out. My plans for buying a new truck will be postponed untill this summer when they give 5k cashback again (Assuming my sources are correct). These bastards just won't give me enough for my 2010 to make a legitment purchase right now =(.
02-14-2011, 10:28 AM
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I'm glad somebody else noticed this, hopefully the OP is still reading. While the prior two posters were correct in their statements that a vehicle tuned for regular unleaded will gain nothing from premium, they missed the fact that the L92 trucks come from the factory tuned for 91+. Because of this, the computer will pull timing if a lower octane fuel is used, and power and efficiency will suffer.