2019 GLC63 - Ready to try more aggressive maps

[rowdytn]

(I posted this in the support and logs group, but realized I probably should have posted here)

For the past year plus, I've been running 93 Octane on Map 2 in my 2019 GLC63 every day. I've never thrown a code, and love how it runs. When I first installed the JB4, I read about issues running ethanol mixes and decided Map 2 was enough and I'd never need ethanol. However, for the past week or so, I've been really getting the itch to try some more aggressive maps.

Can anyone provide me with some suggestions about what mixes and maps to try first? I know George has said some cars handle the mixes better than others. I'd like to see what mine can do, preferably without blowing anything up. My hope is to ease into things, and then add more ethanol to the mix/change maps as the car shows it can tolerate it.

Thank you!

[Terry @ BMS]

Just start with a few gallons of E85, maybe 3-4, and see how the car tolerates it. Fuel pressure is usually the problem with E85 use in these.

[rowdytn]

Thanks, Terry! Would you suggest I run with Map 3 for awhile and then see how it does or if I see any CELs?

[Terry @ BMS]

I'd start with map2 on an E20 mix and see if the fuel pump can handle it. If so then map3 may work.

[bmw-srt]

Bumping this old thread, would upgrading the LPFP give us the ability to run more aggressive "E"-mixes? Or would both the high and low pumps need to be upgraded for that? Low is cheaper to do than high...

[Cannon @ BMS]

Well if you upgrade the LPFP, and the HPFP is still keeping up and is fine, then there's no issues. If the HPFP starts failing, upgrade it.