Gas Options

[PDOT]

I'm lucky to be surrounded by many gas options. After trying to discover which option is the best for performance, I'm still at a loss. Can someone share what has been their best experiences? Price is not a problem as I plan to do this for certain events, but E85 is at a station right at my job so that can be a regular option. I'm currently running 93 Vpower, with a Flash tune, dp, intake.

[13M5F10]

Originally Posted by PDOT

I'm lucky to be surrounded by many gas options. After trying to discover which option is the best for performance, I'm still at a loss. Can someone share what has been their best experiences? Price is not a problem as I plan to do this for certain events, but E85 is at a station right at my job so that can be a regular option. I'm currently running 93 Vpower, with a Flash tune, dp, intake.

Can you elaborate what gas options you have ? I'm assuming up to 93 and E85? Any race has?

I was running 93+3.5 gallons of E85. Nice difference in power between 93 only and + e85

[momos750]

If you have 93 + e85 run that on a regular basis. (20-25% e85 max). Check your fuel trims.

For special events (1/4, 1/2 mile, etc)or when turning up the boost run the highest unleaded octane as you can get. 98-100. Better safety margin and protection against detonation.

[Warrior75]

There are different grades of E85 too? I've never used E85, so not sure.

[momos750]

Originally Posted by Warrior75

There are different grades of E85 too? I've never used E85, so not sure.

Not really different grades. When you mix 93 and e85 you have a different overall percentage of e85. So say your gas tank is 20 gallons, if you add 15 gallons of 93 and 5 gallons of e85, you're effective ratio of e85 is 25%, so e25 +/-. At least that's how I understand it, I could be off.

[Warrior75]

Besides the performance boost, are there any other benefits? I almost want to say I remember when I was active in the M5board, people were trying to avoid gas with ethanol. Did the position change or am I remembering incorrectly?

[momos750]

Originally Posted by Warrior75

Besides the performance boost, are there any other benefits? I almost want to say I remember when I was active in the M5board, people were trying to avoid gas with ethanol. Did the position change or am I remembering incorrectly?

It's not really to raise performance unless you have a e85 specific tune. E85 raises your effective octane and therefor provides more of a safety margin.
I'm not sure which car you're referring
to hearing about in the past. If it was an E39 or E60 M5 N/A car, those cars are target based cars and running e85 would make them run lean.
The new F10's twin turbos are set up differently and allow smaller amounts of e85 to be ran safely. Again---need to monitor your fuel trims to know exactly what's safe for your application.

[Warrior75]

Yes, E60 M5 and E6X M6, the S85 V10. That clears it up, thank you for the information.

[momos750]

Originally Posted by Warrior75

Yes, E60 M5 and E6X M6, the S85 V10. That clears it up, thank you for the information.

It's just my understanding, I'm by no means an expert.

[PDOT]

Originally Posted by 13M5F10

Can you elaborate what gas options you have? Am I assuming up to 93 and E85? Any race has?

I was running 93+3.5 gallons of E85. Nice difference in power between 93 only and + e85

Sorry so I have 1-speed shop that carries VP (C16, MS109) and a Sunoco that carries racing gas too (GT260 and 260+).

[M6-Coupe]

From User's Manual:

Do not refuel with any leaded gasoline or gasoline with metallic additives, e. g. manganese or iron, or permanent damage to the catalytic converter and other components.

Fuels with a maximum ethanol content of 10 %, i. e., E10, may be used for refueling. Ethanol should satisfy the following quality standards: US: ASTM 4806–xx CAN: CGSB-3.511–xx xx: comply with the current standard in each case.
Do not refuel with ethanol E85 Do not refuel with E85, i.e., fuel with an ethanol content of 85 %, or with Flex Fuel, as this would damage the engine and fuel supply system.

The engine is knock controlled. Therefore, you can refuel with different gasoline qualities.
Recommended fuel quality BMW recommends AKI 93.
Minimum fuel grade BMW recommends AKI 91.
Do not use any gasoline below the minimum fuel grade as this may impair engine performance.

If you use gasoline with this minimum AKI Rating, the engine may produce knocking sounds when starting at high outside temperatures. This has no effect on the engine life. Minimum fuel grade The use of poor-quality fuels may result in harmful engine deposits or damage. Additionally, problems relating to drivability, starting and stalling, especially under certain environmental conditions such as high ambient temperature and high altitude, may occur. If drivability problems are encountered, we recommend switching to a high quality gasoline brand and a higher octane grade — AKI number — for a few tank fills. To avoid harmful engine deposits, it is highly recommended to purchase gasoline from BP or Top Tier retailers. Failure to comply with these recommendations may result in the need for unscheduled maintenance.