Little Confusion with Map 2, 5, & 7.

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Hey everyone sorry for the typical n00b, "which map should I use" question but after some research I can not get a solid answer.

My mods include: JB4 G5 ISO (27.1), BMS 3" catless downpipes, BMS DCIs, BMS cowl filters, and usually I run 30%-50% E85. 2009 N54 135i.

Stock fuel pump
6spd

Now my questions are, for daily driving should I have it kept in Map 2 or Map 5? I'm assuming Map 5 since it is self-adapting to mods, weather, fueling, etc. With Map 5 on e85 mix or 93 full tank I peak and hold 16psi, but without e85 should I have it in Map 2?

Now for the rare occasion friendly runs and the track should I switch to Map 7? There seems to be much controversy on this question. I have heard Terry say that with a 50/50 mix of e85 and 93 I can run Map 7. Although after emailing Terry last night he responded (or one of his staff) that I need this "BMS flash" and the walbro 450lph e85 pump in order to run Map 7.

Any truth to this? Looking to get opinions here. Any help will be greatly appreciated!

[BEAR-AvHistory]

Map 5 without the BMS flash. You are a bit short on octane for Map 7. By the time you mix in enough E85 you will be having fueling problems.

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Originally Posted by BEAR-AvHistory

Map 5 without the BMS flash. You are a bit short on octane for Map 7. By the time you mix in enough E85 you will be having fueling problems.

Can you explain what exactly this backend flash?

[BEAR-AvHistory]

The BMS backend flash is a modification (flash) of the ECU using either a COBB or BT cable. Terry has written custom Maps for the COBB that co-exist with the normal JB4 firmware. With it you are “stacking” both tunes, JB4/ISO – COBB for a better overall result than either can produce on its own. Uses the best features of both worlds. One of the test cars a 335IS driven by MDyates ran the 1/4 in IIRC 11.8/9? @ 118mph with a pure stock car including RFT’s & a mix of E85/93 octane.

I don’t know what his mix was but without the BMS flash I was limited to approximately 60/40 93/E85. I used to put in 6 gals of E85 on a fill-up with 93 till the E85 station closed. I now run 50/50 93/100 with 8gals of 100 per fill-up.

I am in the process of fine tuning the stack for this fuel mix. The 135is has an N55 so I just did the JB4 & left everything else stock & run only 93 in it. The 335IS has in addition to the JB4/COBB an ETS 5"FMIC, Drop In BMS filter element & 245/265 Conti DW tires. All else is pure stock.

EDIT: firmware is up to 27.3

[..]

Originally Posted by BEAR-AvHistory

The BMS backend flash is a modification (flash) of the ECU using either a COBB or BT cable. Terry has written custom Maps for the COBB that co-exist with the normal JB4 firmware. With it you are “stacking” both tunes, JB4/ISO – COBB for a better overall result than either can produce on its own. Uses the best features of both worlds. One of the test cars a 335IS driven by MDyates ran the 1/4 in IIRC 11.8/9? @ 118mph with a pure stock car including RFT’s & a mix of E85/93 octane.

I don’t know what his mix was but without the BMS flash I was limited to approximately 60/40 93/E85. I used to put in 6 gals of E85 on a fill-up with 93 till the E85 station closed. I now run 50/50 93/100 with 8gals of 100 per fill-up.

I am in the process of fine tuning the stack for this fuel mix. The 135is has an N55 so I just did the JB4 & left everything else stock & run only 93 in it. The 335IS has in addition to the JB4/COBB an ETS 5"FMIC, Drop In BMS filter element & 245/265 Conti DW tires. All else is pure stock.

EDIT: firmware is up to 27.3

Terry seems to have a new update every week for the firmware!

Thank you for that detailed response!

Now this BT cable, from the looks of it on burgertuning's website is the cable you use to code your car, correct?

[BEAR-AvHistory]

Yes the $187 BT cable will code the car with the back end flash. BUT BUT its an exacting process. You need to go to a site we can't mention here along with Terry's forum site to get additional info.

As far as I know for whom ever it applies to there is no plan to extend it to cover the 335is, they will be COBB based.

Yes on the updates. A number of us run with all the new releases & provide data back to Terry. Those not interested in playing with the new stuff stay with one of the older firmware uploads.

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I always leave it in map 5 and never go over 40-50% e85 since I do not have the walbro 255 fuel pump yet. Every other fill up I do 100% 93 octane. I dont know if it is the Map 5 constantly adjusting but for some reason there will be days where my car is running so strong it will lose control in 2nd gear WOT, and yet some days while making the same psi (15-16) I am not making the same power; won't break traction like other days. Could this be because of Map 5 constantly adjusting? Or is it because I do not consecutively run e85 mixes?

I would prefer for it to always run aggressively to have the power I want at my disposal.

[Nugget]

If you significantly change your fuel mix them you need to change out of map 5 and then change back and let it readapt with a few 3rd gear pulls.

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Originally Posted by Nugget

If you significantly change your fuel mix them you need to change out of map 5 and then change back and let it readapt with a few 3rd gear pulls.

Yes, I think best bet is to now stick with consecutive e85 mixes