OFT Stage 2+ E85 better MPG than 91 octane - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

Phoenix000000 · 09-05-2021, 03:41 PM

Been running OFT Stage 2+ v4.03 (on 91 octane) for six months averaging 23-24 MPG. Swapped over to Stage 2+ E85 v4.03 about a month ago (running E85 octane obviously) and noticed my MPG increase to 27-29 MPG. No new mods or changes to the tune. Didn't change how I drive. I'm just curious if anyone else has encountered the same change. I was always under the impression I'd lose around 30% MPG on E85 vs 91 octane.

Car:
2017 Subaru BRZ 2017 Performance Package

ECU:
OFT Stage 2+ E85 v4.03

Intake:
K&N Cold Air Intake Kit

Exhaust:
Tomei Expreme UEL Header
Tomei Expreme Over Pipe
Magnaflow 15157 Cat Back Exhaust

Tires:
Michelin Pilot Sport All Season 4 - 215/45ZR17

Lantanafrs2 · 09-05-2021, 03:49 PM

Check mileage between fill ups. Dont look at the dash display

gen3v8 · 09-05-2021, 05:48 PM

Something wrong

Dzmitry · 09-08-2021, 01:53 PM

Quote:

Originally Posted by Phoenix000000

Been running OFT Stage 2+ v4.03 (on 91 octane) for six months averaging 23-24 MPG. Swapped over to Stage 2+ E85 v4.03 about a month ago (running E85 octane obviously) and noticed my MPG increase to 27-29 MPG. No new mods or changes to the tune. Didn't change how I drive. I'm just curious if anyone else has encountered the same change. I was always under the impression I'd lose around 30% MPG on E85 vs 91 octane.

Car:
2017 Subaru BRZ 2017 Performance Package

ECU:
OFT Stage 2+ E85 v4.03

Intake:
K&N Cold Air Intake Kit

Exhaust:
Tomei Expreme UEL Header
Tomei Expreme Over Pipe
Magnaflow 15157 Cat Back Exhaust

Tires:
Michelin Pilot Sport All Season 4 - 215/45ZR17

Yes, it is literally impossible for you to get the same or better gas mileage if running the car the same as you always have. The dash does not display the correct gas mileage, you have to do your own calculation based on your fill-ups. With a proper tune, there is some improvement in efficiency, so to a certain extent you may have "improved" gas mileage, but with E85 it will definitely be quite a bit lower.

Celica00 · 09-08-2021, 03:06 PM

91 I was averaging 28-30 mpg
E85 averaging 22-23 mpg

The loss in mpg is just slightly more costly than the savings of the cheaper fuel in my area. Wow that sentence hurt my head.

Worth it, but I have no idea how you're making more mpg

Westen86 · 09-08-2021, 06:03 PM

OFT V4 flash on E85 and doing 18-20mpg

CincyJohn · 09-13-2021, 09:22 AM

Quote:

Originally Posted by Westen86

OFT V4 flash on E85 and doing 18-20mpg

Me too. No way to get better gas mileage on e85.

Jaden · 09-22-2021, 12:59 PM

If the calculations for mileage aren't changed it won't read correctly. I don't know how you were getting only 22-23 on 91 as I would get 36 for long highway trips and 28-29 when averaging locally.

On E52 (best I can find in Arizona) I now drive almost exclusively city and I get like 17-18

Jaden

09-05-2021, 03:41 PM	#1
Phoenix000000 Junior Member Join Date: Sep 2021 Drives: 2017 Subaru BRZ PP WRB Location: Colorado Posts: 2 Thanks: 0 Thanked 0 Times in 0 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	OFT Stage 2+ E85 better MPG than 91 octane Been running OFT Stage 2+ v4.03 (on 91 octane) for six months averaging 23-24 MPG. Swapped over to Stage 2+ E85 v4.03 about a month ago (running E85 octane obviously) and noticed my MPG increase to 27-29 MPG. No new mods or changes to the tune. Didn't change how I drive. I'm just curious if anyone else has encountered the same change. I was always under the impression I'd lose around 30% MPG on E85 vs 91 octane. Car: 2017 Subaru BRZ 2017 Performance Package ECU: OFT Stage 2+ E85 v4.03 Intake: K&N Cold Air Intake Kit Exhaust: Tomei Expreme UEL Header Tomei Expreme Over Pipe Magnaflow 15157 Cat Back Exhaust Tires: Michelin Pilot Sport All Season 4 - 215/45ZR17

09-05-2021, 05:48 PM	#3
gen3v8 Barred Join Date: Oct 2020 Drives: My18 wrxsti My19 brzts Location: Botany Bay Posts: 1,144 Thanks: 730 Thanked 1,187 Times in 610 Posts Mentioned: 7 Post(s) Tagged: 0 Thread(s)	Something wrong __________________ Wait until my Flex capacitor hits 88

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09-05-2021, 03:49 PM	#2
Lantanafrs2 Senior Member Join Date: Jan 2018 Drives: 2013 frs red Location: South Florida Posts: 3,517 Thanks: 2,520 Thanked 3,088 Times in 1,654 Posts Mentioned: 6 Post(s) Tagged: 1 Thread(s)	Check mileage between fill ups. Dont look at the dash display

09-08-2021, 03:06 PM	#5
Celica00 Senior Member Join Date: Sep 2012 Drives: 86 Location: utah Posts: 1,156 Thanks: 842 Thanked 798 Times in 434 Posts Mentioned: 8 Post(s) Tagged: 2 Thread(s)	91 I was averaging 28-30 mpg E85 averaging 22-23 mpg The loss in mpg is just slightly more costly than the savings of the cheaper fuel in my area. Wow that sentence hurt my head. Worth it, but I have no idea how you're making more mpg

09-22-2021, 12:59 PM	#8
Jaden Road-hole Join Date: Jul 2014 Drives: 2013 Whiteout FR-S Location: Gilbert, Arizona Posts: 1,112 Thanks: 272 Thanked 479 Times in 292 Posts Mentioned: 13 Post(s) Tagged: 0 Thread(s)	If the calculations for mileage aren't changed it won't read correctly. I don't know how you were getting only 22-23 on 91 as I would get 36 for long highway trips and 28-29 when averaging locally. On E52 (best I can find in Arizona) I now drive almost exclusively city and I get like 17-18 Jaden

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