[CrzyChris5]

So I have a 2017 X4 M40i and there is no real information out there as far as specific changes made to this car's engine, suspencion, exhaust, etc. All i get is "engine has been tuned to provide 360 hp". What else did they change? Better FMIC? Higher flow cats? Anyone know?

I was looking into getting MHD flasher tune installed and they usually recommend Stage 1 flash for a stock X4 and a Stage 2 flash if you have upgraded FMIC, charge pipe, high flow cats, etc. When i emailed them about my stock X4 M40i, they only offer stage 2 flash for it. Do they think the car also comes with all these components already upgraded? As far as i can find, the X4M still has same parts as the regular X4 and just has some engine tweaks to make it faster, but i could be wrong.

So what are all the upgrades this car comes with?

[DBU]

Originally Posted by CrzyChris5

So I have a 2017 X4 M40i and there is no real information out there as far as specific changes made to this car's engine, suspencion, exhaust, etc. All i get is "engine has been tuned to provide 360 hp". What else did they change? Better FMIC? Higher flow cats? Anyone know?

I was looking into getting MHD flasher tune installed and they usually recommend Stage 1 flash for a stock X4 and a Stage 2 flash if you have upgraded FMIC, charge pipe, high flow cats, etc. When i emailed them about my stock X4 M40i, they only offer stage 2 flash for it. Do they think the car also comes with all these components already upgraded? As far as i can find, the X4M still has same parts as the regular X4 and just has some engine tweaks to make it faster, but i could be wrong.

So what are all the upgrades this car comes with?

Upgrades from what? I mean, what are you trying to compare with?
We share the motor (N55B30T0) with the M2. Search that forum and the internet in general.

[CrzyChris5]

Originally Posted by DBU

Upgrades from what? I mean, what are you trying to compare with?
We share the motor (N55B30T0) with the M2. Search that forum and the internet in general.

Comparing it to the regular X4 35i. What is upgraded from that to the M40i? Tuners are telling me the X4 M40i is good for stage 2 tunes whereas the X4 35i can only handle Stage 1 tunes. So i want to know why is the X4 m40i ok to handle stage 2 tunes. Must have more upgraded components than just boost tweaks, etc

[hpotter]

X4 35i has N55B30M0 engine, while M40i has N55B30T0. Use following chart you can see M = medium output, T = top output. So the engine is the same, but maybe bmw used more durable parts for the M40i to handle more power.

http://f87.bimmerpost.com/forums/sho....php?t=1042283

[CrzyChris5]

Originally Posted by hpotter

X4 35i has N55B30M0 engine, while M40i has N55B30T0. Use following chart you can see M = medium output, T = top output. So the engine is the same, but maybe bmw used more durable parts for the M40i to handle more power.

http://f87.bimmerpost.com/forums/sho....php?t=1042283

Thanks

[CrzyChris5]

Also just found this which answers my question better.

"The M40i’s unit was constructed with a closed-deck design, meaning that the water jacket surrounding the cylinders is sealed at the top, endowing the crankcase with an exceptionally high degree of stiffness.

BMW also gave it a new oil cooler, high pressure injectors, turbos integrated into the exhaust manifold operating at a higher boost, an optimized air intake manifold, a forged crankshaft, pistons with a modified top ring and high-performance spark plugs, and upgraded steering response."

[FSociety]

Originally Posted by CrzyChris5

Also just found this which answers my question better.

"The M40i’s unit was constructed with a closed-deck design, meaning that the water jacket surrounding the cylinders is sealed at the top, endowing the crankcase with an exceptionally high degree of stiffness.

BMW also gave it a new oil cooler, high pressure injectors, turbos integrated into the exhaust manifold operating at a higher boost, an optimized air intake manifold, a forged crankshaft, pistons with a modified top ring and high-performance spark plugs, and upgraded steering response."

yessir

[doodlebro]

Originally Posted by CrzyChris5

Also just found this which answers my question better.

"The M40i’s unit was constructed with a closed-deck design, meaning that the water jacket surrounding the cylinders is sealed at the top, endowing the crankcase with an exceptionally high degree of stiffness.

BMW also gave it a new oil cooler, high pressure injectors, turbos integrated into the exhaust manifold operating at a higher boost, an optimized air intake manifold, a forged crankshaft, pistons with a modified top ring and high-performance spark plugs, and upgraded steering response."

Not sure where you got that, but I looked into the oil cooler at least, and it's the same as the one on the X3 35i:

X4 Oil cooler: http://www.realoem.com/bmw/enUS/show...84#17217601536

X3 Oil cooler: http://www.realoem.com/bmw/enUS/show...84#17217601536

I don't have the time now, but I want to dig into this some more and determine the true engine differences.

Edit:

Air Intake manifold is the same.
Injectors appear to be the same, I compared the high pressure fuel system from both but I may have missed something.
Crankshaft is different and is same one used on M2.
Turbo is different, looks like the made it only for the X4 40i, but all BMWs from this era have the turbo integrated into the exhaust manifold.
Spark plugs are different brands, but I don't know if that means they are different in practice.
Pistons are different