[BMWtight2me]

I have a 320i (jb4, DP, FMIC, CAI, exhaust, etc.) and I typically run 91 octane and use maps 1 and 5 (I prefer map 1). I love map 2, but typically only use it when I fill up with a higher blend octane (93+). However lately it's been cold out 50-70 degrees and I have been testing map 2 with 91 octane and it runs nice and smooth. Dare I say it feels smoother than map 1? Definitely faster too! Would love to run map 2 on 91 regularly. Anyone do this?

What are your thoughts, and what's your experience experimenting with different maps and fuels? I'd love to find the best possible set up. 320 and 328 oppinions welcome!

[smallba]

13' 328i xDrive n20 EWG JB4, GFB DV+ , S55 Plugs, 97 or 98 (30% ish E85 blend w/93), I use Map 2, got some future plans this spring

[mike@x-ph.com]

Originally Posted by BMWtight2me

I have a 320i (jb4, DP, FMIC, CAI, exhaust, etc.) and I typically run 91 octane and use maps 1 and 5 (I prefer map 1). I love map 2, but typically only use it when I fill up with a higher blend octane (93+). However lately it's been cold out 50-70 degrees and I have been testing map 2 with 91 octane and it runs nice and smooth. Dare I say it feels smoother than map 1? Definitely faster too! Would love to run map 2 on 91 regularly. Anyone do this?

What are your thoughts, and what's your experience experimenting with different maps and fuels? I'd love to find the best possible set up. 320 and 328 oppinions welcome!

Datalog and check how the car is handling map 2 boost

[BMWtight2me]

Originally Posted by mike@x-ph.com

Datalog and check how the car is handling map 2 boost

Looks good rn. I'll keep checking as the temperature changes. Really surprised by the power. Feels quicker than the m235i.

[BMWtight2me]

Is anyone running map 2 on 91?

[smallba]

Originally Posted by BMWtight2me

Is anyone running map 2 on 91?

Do a log an see if you car can hold boost at that octane without pulling timing. I would really suggest running 93 octane or higher on a n26 on map 2 daily, but definitely get a log

[BMWtight2me]

Originally Posted by smallba

Do a log an see if you car can hold boost at that octane without pulling timing. I would really suggest running 93 octane or higher on a n26 on map 2 daily, but definitely get a log

Logged well on 93. Don't feel the timing dropping on 91. I have a blend in now (93ish), I'll try to do some logs with this tank and follow up with some 91 oct runs after

[BMWtight2me]

Btw -- it's the n20 not the n26. Not sure if there are any critical differences in those engines that would change the outcome of what octane I'm running, but I just wanted to be clear about my set up.

[Stubok]

Originally Posted by BMWtight2me

Btw -- it's the n20 not the n26. Not sure if there are any critical differences in those engines that would change the outcome of what octane I'm running, but I just wanted to be clear about my set up.

Pretty sure the main difference between N20 and N26 is the Cat. N20 is 600cell and N26 is 900 cell or something like that. Of course the stock tune might be altered for the additional back pressure in the N26.

So with down pipe they should be virtually the same.

Though JB4 in theory could effect the stock tunes differently.

[smallba]

Originally Posted by BMWtight2me

Btw -- it's the n20 not the n26. Not sure if there are any critical differences in those engines that would change the outcome of what octane I'm running, but I just wanted to be clear about my set up.

sorry i don't know why i assumed that, the difference is between the 328 and 320 n20/26 motors being the 320 motors have different pistons and tuned differently. I believe the exhaust diameter may be different as well but don't quote me on that.

Stubok explained the main difference between the n20 and the n26. Heres one some more details:

"The differences between the N20 (7/2012 and on) and N26 are tiny. Pre 7/2012 N20*engines*had a vacuum driven waste*gate, where newer N20s and N26s have electronically driven waste gates.*

Catalytic Converter
N26 - first monolith: 900 cpsi, second monolith: 600cpsi) "Cells Per Square Inch". There is an additional*catalytic converter*located under the vehicle downstream of theexhaust. This converter is not monitored and contains 400 cpsi.
N20 - 600 cpsi on the first monolith and 400 cpsi on the second.

Cylinder Head*Cover
N26*oil*separators are made of plastic and are very similar to those in the N20*engine. The major change to thecylinder head*cover is that the*crankcase pressure regulating valve*is now plastic welded to the cover and no longer to be replaced separately.

High Pressure Fuel Pump
The*HP pump*has been slightly redesigned for the N26engine. It has been modified by adding a groove in the outlet valve of the*high pressure pump. This allows the*high fuel pressure*to be reduced in a short amount of time when the*engine*is shut off. This reduces the risk of internal and external fuel leakage.

Fuel Injectors
The fuel injectors used in the N26 are identical to the N20 and N55 from a technical point of view. The major difference is the N26 injectors are hand selected after they have been tested to insure they have the minimum amount of leakage. These are referred to as "Sorted" fuel injectors. They have a leakage rate of <0.5mm³/min @20MPa.

Fuel Line
The*fuel*lines have been modified to insure that no leakage occurs.

Air box
The*air intake system*is similar to the M56 and N51 SULEV engines. There is an additional HC fleece filter installed in the air box. This prevents hydrocarbons from escaping to the atmosphere when the*engine*is at rest. The HC fleece is part of the upper portion of the air box and needs to be replaced as a complete unit if damaged.

Cooling System
The*radiator*of the N26 SULEV looks similar to the standard F30*radiator. The surface of the cooling fins are coated with a special "PremAir" coating. The coating consists of multiple porous layers of a catalytic surface. The task of the catalyst coating is to convert Ozone into Oxygen."

[BMWtight2me]

Originally Posted by smallba

sorry i don't know why i assumed that, the difference is between the 328 and 320 n20/26 motors being the 320 motors have different pistons and tuned differently. I believe the exhaust diameter may be different as well but don't quote me on that.

Stubok explained the main difference between the n20 and the n26. Heres one some more details:

"The differences between the N20 (7/2012 and on) and N26 are tiny. Pre 7/2012 N20*engines*had a vacuum driven waste*gate, where newer N20s and N26s have electronically driven waste gates.*

Catalytic Converter
N26 - first monolith: 900 cpsi, second monolith: 600cpsi) "Cells Per Square Inch". There is an additional*catalytic converter*located under the vehicle downstream of theexhaust. This converter is not monitored and contains 400 cpsi.
N20 - 600 cpsi on the first monolith and 400 cpsi on the second.

Cylinder Head*Cover
N26*oil*separators are made of plastic and are very similar to those in the N20*engine. The major change to thecylinder head*cover is that the*crankcase pressure regulating valve*is now plastic welded to the cover and no longer to be replaced separately.

High Pressure Fuel Pump
The*HP pump*has been slightly redesigned for the N26engine. It has been modified by adding a groove in the outlet valve of the*high pressure pump. This allows the*high fuel pressure*to be reduced in a short amount of time when the*engine*is shut off. This reduces the risk of internal and external fuel leakage.

Fuel Injectors
The fuel injectors used in the N26 are identical to the N20 and N55 from a technical point of view. The major difference is the N26 injectors are hand selected after they have been tested to insure they have the minimum amount of leakage. These are referred to as "Sorted" fuel injectors. They have a leakage rate of <0.5mm³/min @20MPa.

Fuel Line
The*fuel*lines have been modified to insure that no leakage occurs.

Air box
The*air intake system*is similar to the M56 and N51 SULEV engines. There is an additional HC fleece filter installed in the air box. This prevents hydrocarbons from escaping to the atmosphere when the*engine*is at rest. The HC fleece is part of the upper portion of the air box and needs to be replaced as a complete unit if damaged.

Cooling System
The*radiator*of the N26 SULEV looks similar to the standard F30*radiator. The surface of the cooling fins are coated with a special "PremAir" coating. The coating consists of multiple porous layers of a catalytic surface. The task of the catalyst coating is to convert Ozone into Oxygen."

Great info! Thanks.

[D041987]

Almost looks like the N26 is the better engine if modding, haha. Just need to get a new Exhaust/DP, Intake, and Tune and you have a overall better quality motor!