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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

different octane, different MPG?

  • Thread starter Thread starter fivespeedsteed
  • Start date Start date May 23, 2007

fivespeedsteed

20+ Year Stangneter
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#1
  • May 23, 2007
  • #1
i was trying to think i have about a halftank of 93 in my car now and it seems to be lasting a little better than usual. ive been running 89 this whole time. does it last longer? the higher it is the longer it lasts?
 
B

Boss 351

Here sthhhhhhhheeeve take a picthh of my man flowe
Jul 13, 2003
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#2
  • May 23, 2007
  • #2
don't know anymore, I keep getting told that it's a myth though. If the car is timed for 89 then run it with 89....
 

jrichker

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#3
  • May 23, 2007
  • #3
Higher octane gasoline usually includes a more expensive additive package. That additive package may include fuel system cleaners and mileage improvements.
 

fivespeedsteed

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#4
  • May 23, 2007
  • #4
thats what i figured, i was just wondering however because my throttle response and car in general feels a little more responsive.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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#5
  • May 23, 2007
  • #5
In theory, the lower the octane you can safely run on your car, the more efficient the fuel will burn therefor more power and better milage.

Of course every car is different, but that's the theory around octane levels.


I hate explaining that when people see me filling my car up with 87 and say "You put the cheap stuff??? You should toss in 93 and make more power!!"
 

Darkwriter77

Resident Ranting Negative Nancy
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#6
  • May 23, 2007
  • #6
It's probably just your foot being lighter on the gas pedal, because you know that the more you step on it, the faster that extra-expensive gas will go away...
 

fivespeedsteed

20+ Year Stangneter
Oct 17, 2003
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Richmond, VA
May 23, 2007
#7
  • May 23, 2007
  • #7
oh i didnt know that that lower octane burns better and is more effecient
 

wythors

Get off my lawn!!!
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#8
  • May 23, 2007
  • #8
jrichker said:
Higher octane gasoline usually includes a more expensive additive package. That additive package may include fuel system cleaners and mileage improvements.
Click to expand...

Which was a large reason for my switch many years ago from cheapo gas to "name brand" gas. I noted an immediate uptick of almost 2 mpg.
 

Darkwriter77

Resident Ranting Negative Nancy
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#9
  • May 23, 2007
  • #9
The Notch gets 91 octane. I can't run 89 octane with my timing advanced to 14* without getting pinging (sadly).

The TurdBird gets plain ol' 87 octane.

Both cars get their meals almost exclusively at QuikTrip ... and so do I, now that they've started carrying those Über-yummy taquitos and "stuffed breadsticks." It's cheaper eatin' than Taco Bell, and just as bad for you!
 

FrankenStang

Now, give me a damn CT!
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#10
  • May 23, 2007
  • #10
Darkwriter77 said:
The Notch gets 91 octane. I can't run 89 octane with my timing advanced to 14* without getting pinging (sadly).

The TurdBird gets plain ol' 87 octane.

Both cars get their meals almost exclusively at QuikTrip ... and so do I, now that they've started carrying those Über-yummy taquitos and "stuffed breadsticks." It's cheaper eatin' than Taco Bell, and just as bad for you!
Click to expand...


They've carried those taquitos for a long time now. Those things are addicting.
 

Darkwriter77

Resident Ranting Negative Nancy
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#11
  • May 23, 2007
  • #11
Don't mind me. I'm just slow to catch onto these new fangled fads you youngsters are all picking up on.
 

Aftrbrnr

Whitey cashier gave me the wrong change at the sup
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#12
  • May 23, 2007
  • #12
One of my friends told me that you get better mileage with premium, but I don't know if I buy it. Also, the increased MPG if true is off-set by the higher gas price, so in the end I think it isn't any cheaper.

I think based on the low compression of the stock 5.0, I've been told there is no benefit of higher octane fuel for those cars.
 

Darkwriter77

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May 24, 2007
#13
  • May 24, 2007
  • #13
...unless you're running higher octane because you've bumped the timing, which DOES benefit your power a little bit.
 

stykthyn

I want to measure mine. It doesn't look that tall.
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#14
  • May 24, 2007
  • #14
higher octane fuel is desinged to burn longer under compression. under higher compression the longer burn will keep the engine from detonating. running higher octane in an engine that is not timed or designed to run it will over time leave deposits from unburned fuel. figure premium runs .20 more than regualr octane. in a 15 gallon tank that is around 3.00, go buy a bottle of fuel additive. your car will run just as smooth if not better.
 
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