[KRAZSMILEZ18]

Hey guys, so I need some help. Super new to this and I need to learn more please! I’m not sure if I should be looking at boots and/or what I should be running in my car. I have a 2015 bmw m235i xdrive n55 with a catless DP, an intake, and the jb4 tune. Currently I’m running it on map 6 with the certain boxes filled out, and I need to know what I should change up a bit. Very confused on if I throw these numbers in the boxes and use map 2, if it even will work like that. I am at 30% e85 and the rest 91 octane here in Colorado. I am not running close to that 17 boost and I’m not sure if I should even be looking at ecu_psi or “boost” through everything. Need some major help!😂🤷🏼*♂️

[sdhasher21]

You should probably move to map 5 for now. Map 6 is for custom tune and not one you want to mess with yourself unless you know what you're doing. Map 5 is adaptive. I'm running a similar setup as you on map 5 and it's been good. I'd check n54tech for more info, since that's the Jb4 guys' forum.

Also, your IAT is pretty high. I'm in Southern CA and the max for me has been 120, but usually around 100-108 on a hot day (85 degrees). I also upgraded my intercooler, though.

Not sure how the high altitude for you comes into play, but I'd switch to map 5 ASAP or map 2.

[KRAZSMILEZ18]

Originally Posted by sdhasher21

You should probably move to map 5 for now. Map 6 is for custom tune and not one you want to mess with yourself unless you know what you're doing. Map 5 is adaptive. I'm running a similar setup as you on map 5 and it's been good. I'd check n54tech for more info, since that's the Jb4 guys' forum.

Also, your IAT is pretty high. I'm in Southern CA and the max for me has been 120, but usually around 100-108 on a hot day (85 degrees). I also upgraded my intercooler, though.

Not sure how the high altitude for you comes into play, but I'd switch to map 5 ASAP or map 2.

Yeah I changed it to map 2 and it runs about 15.4 boost and it's pretty fast, but do those even matter to write those down when I'm in map 2? Or is that strictly for map 6?

[sdhasher21]

Originally Posted by KRAZSMILEZ18

Yeah I changed it to map 2 and it runs about 15.4 boost and it's pretty fast, but do those even matter to write those down when I'm in map 2? Or is that strictly for map 6?

Easiest way to check is take a look at the settings when in another map. Definitely recommend emailing Terry at BMS or visit the above forum, as it has a lot of good info.

[KRAZSMILEZ18]

Originally Posted by sdhasher21

Easiest way to check is take a look at the settings when in another map. Definitely recommend emailing Terry at BMS or visit the above forum, as it has a lot of good info.

Ok cool. And do you know if I can run full e85 on map 5 or even full on map 2? Which one makes more power?

[sdhasher21]

Originally Posted by KRAZSMILEZ18

Ok cool. And do you know if I can run full e85 on map 5 or even full on map 2? Which one makes more power?

Usually can't run 100% e85 without some serious fuel upgrades. One thing I will say is to log a lot and learn to read the logs.

[KRAZSMILEZ18]

Originally Posted by sdhasher21

Usually can't run 100% e85 without some serious fuel upgrades. One thing I will say is to log a lot and learn to read the logs.

I put it in map 5 again with that 30% e85 and I'm getting really low boost

[KRAZSMILEZ18]

Originally Posted by KRAZSMILEZ18

I put it in map 5 again with that 30% e85 and I'm getting really low boost

Barely getting even 12.9 psi

[Pray for Mojo]

You aren't going to get a ton more boost given you live at altitude. Do the math between where you live and sea level, most guys making 17-18 are at sea level not 5,000 ft.

[KRAZSMILEZ18]

Originally Posted by Pray for Mojo

You aren't going to get a ton more boost given you live at altitude. Do the math between where you live and sea level, most guys making 17-18 are at sea level not 5,000 ft.

So I should stay on map 2 then most likely.

[Pray for Mojo]

Map 2 is probably the upper limit for the stock turbo at altitude, even at 15psi you are beyond the efficiency range of the stock turbo, which means it could wear out quicker. I'm only at 3,200ft and mine struggles to make 15-16psi on a flash tune.

[KRAZSMILEZ18]

Originally Posted by Pray for Mojo

Map 2 is probably the upper limit for the stock turbo at altitude, even at 15psi you are beyond the efficiency range of the stock turbo, which means it could wear out quicker. I'm only at 3,200ft and mine struggles to make 15-16psi on a flash tune.

I'm making 15.9 psi on map 2

[Pray for Mojo]

You can make that boost, but it will make a bunch more heat and potentially wear out the turbo. What altitude are you actually at? Map 2 is absolute so it will force the wastegate closed and make the boost no matter what, it's debatable whether its a good idea though.

[KRAZSMILEZ18]

Originally Posted by Pray for Mojo

You can make that boost, but it will make a bunch more heat and potentially wear out the turbo. What altitude are you actually at? Map 2 is absolute so it will force the wastegate closed and make the boost no matter what, it's debatable whether its a good idea though.

Interesting. Idk the exact altitude, but it's Arvada, CO

[Pray for Mojo]

Wikipedia says 5,300ft. If you look at the real barometric pressure on a weather app and compare it to sea level you are probably down like 20% absolute pressure. At 3,200ft I make 15% less boost with wastegate duty cycle at 100% at 6,200rpm.

[Pray for Mojo]

I'd personally run map 5, 80% of 17psi is 13.6psi. The actual math would depend on the real pressure differential. You aren't missing anything since every car in Colorado is down on power compared to sea level.

[KRAZSMILEZ18]

Originally Posted by Pray for Mojo

I'd personally run map 5, 80% of 17psi is 13.6psi. The actual math would depend on the real pressure differential. You aren't missing anything since every car in Colorado is down on power compared to sea level.

I hate altitude. But thank you for your help. I may have to check more on everything!

[Pray for Mojo]

It sucks, I know all too well. The only reason the stock turbos have the available head room is folks at altitude. BMW leaves enough room so the dude in the Andes at 8,000ft is making stock power.

[KRAZSMILEZ18]

Originally Posted by Pray for Mojo

It sucks, I know all too well. The only reason the stock turbos have the available head room is folks at altitude. BMW leaves enough room so the dude in the Andes at 8,000ft is making stock power.

Damn