[Stv222]

I have a 2018 BMW 340i GT XDrive. Upgrades are listed below and everything else is stock. I have easy access to high quality 93 octane gas with 10% ethanol or less in it. As well as easy access to E-85 gas with a rating between 51% - 83% Ethanol. (Cleveland Ohio area).

• BMS B58 BILLET INTAKE
• CTS TURBO 400 CELL CATTED DOWNPIPE
• BOOTMOD3 - STAGE 2 ENGINE TUNE
• XHP - STAGE 3 TRANSMISSION TUNE

On Stage 2 /93 Tune, with 93 gas the car runs GREAT. I ran ¼ mile in 11.8 and beat a 2023 C8 stock vet at the track. In this setting the Sport Display shows a max HP of 560. I am topping out around 510. All the math I have done from my track times, and my weight says that I should be somewhere around 505 to 520 HP which lines up with everything else.

On Stage 2 /E30 Tune, with E30 blend gas by mixing 93 and E-85, the car runs good…UNTIL, I give it full throttle. Then car loses all power until I release the throttle a bit, then it backfires and then takes off. This same occurrence happens from a stop and from a rolling 20, 40, 60, and 80 start. Also the Sport Display in the E30 Tune, only shows a max HP of 480.

What I’m curious about…

• Everything I have read says that the E30 Tune should be faster than the 93 Tune. If this is the case, why would the Sport Display show as 93 at 560 HP and E30 at 480 HP?

• Is my issue with the E30 something to do with my stock fuel pump not keeping up?

I would like to know what I can do to get my ¼ mile time to low 11’s, and is an E-blend the answer?

This is also my daily driver, so I am not looking to do anything crazy that will significantly reduce the life of the car.