[symple84]

Which engine yields better tunability, I know the N55 is fairly new but in the long run which of the two will get the significant gains??

[E90Vader]

Lamborghini Gallardo

"nuff said.

[Andrew@ET]

With stock turbos in place the n54 looks to be the victor.

[ciomas]

you've got to be kiddin'

[CPWINCH]

who knows, once theres a turbo upgrade for the n55 we will see. But as of now the n54 is ballin. stoock for stock its the same

[makarov88]

The N55 is like the hidden nine tails power inside naruto... once its released its gonna poo on everything, just wait till the turbo upgrade comes out for it ^^

[IancoleTX]

Originally Posted by makarov88

The N55 is like the hidden nine tails power inside naruto...

wat

[makarov88]

watch naruto and you will understand nub

[zsapphire7]

hahaha

[BoostedE90]

It will be interesting to see what the N55 is capable of once tuners have more time under the hood. But wth that said when it comes to performance BMW prefers to use the N54 (IS model and the new M1). So that must mean something.

[CPWINCH]

Originally Posted by makarov88

The N55 is like the hidden nine tails power inside naruto... once its released its gonna poo on everything^^

most asian thing ever

I was just talking to my friend about naruto 10 minutes ago

[makarov88]

Originally Posted by CPWINCH

most asian thing ever

I was just talking to my friend about naruto 10 minutes ago

but im not asian LOL

[werke-t]

Originally Posted by BoostedE90

It will be interesting to see what the N55 is capable of once tuners have more time under the hood. But wth that said when it comes to performance BMW prefers to use the N54 (IS model and the new M1). So that must mean something.

that right there should be your proof n54 is more capable.

The n55 was out and running when they were deciding on what engine to put in the 1m.

BMW went with the N54 for a reason.

-Travis

[BMWfan07]

I drove an N54 for 3 and half years, now I drive a new N55. I can say without a doubt the N54 is a more powerful engine stock, it just is. I am a bit disappointed in my new car's more pronounced turbo lag. In my previous 335, I punched it in 2nd gear and it was violent, my current car feels more conservative in power delivery.

[CPWINCH]

Originally Posted by makarov88

but im not asian LOL

same

[Jake@PTF]

Gotta love people who answer and have no clue what they are saying.

The factory twins in the n54 will flow more air and ultimately can make more power tuned than the single twin scroll the n55 comes with.

[boostd92]

Currently, N54 can make more power due to twins and upgraded twins that are available.

In terms of *POTENTIAL* ... who knows.... the blocks should be the same strength, the only real difference between the two motors assuming that the tuning side can be solved, is the valvetronic control on the N55... which is a bonus for daily drivers as it yields slightly better gas mileage.

If/when an upgraded single comes out for the N55 it'll be a real crap shoot - till then, N54 is king.

[Aries932]

Originally Posted by FlyLow335i

Gotta love people who answer and have no clue what they are saying.

The factory twins in the n54 will flow more air and ultimately can make more power tuned than the single twin scroll the n55 comes with.

I am curious to see where you got your information as well...considering nobody has any clue as to what the cfm(a measure of the flow rate) is of the turbo on the N55...people do not even know what turbo it is besides the fact that it is from borg warner.

What I do know is that the N55 turbo is larger than the N54 turbos so could you please cite me your sources explaining how you came up with a larger cfm number?

My guess is that you are also just answering without knowing.

[Aries932]

This is thanks to Drakel and Turbolader for putting this together

Here's the differences I can find. IMO, the differences are "evolutionary" with exception of the Valvetronic system and much simpler oiling system. I have a feeling the N55 is going to be easier on oil than the N54.

N54: Some cams are cast, some are lightweight hollow
N55: All cams are lightweight hollow

N54: Vacuum pump gets oiled by unfiltered oil
N55: Vacuum pump gets oiled by filtered oil

N54: Connecting rods (small ends) do not have a hole
N55: Connecting rods (small ends) have a hole (Which distributes load better)

N54: Crank is forged, weighs approx 23.3Kg
N55: Crank is case, weighs approx 20.3Kg

N54: PCV system uses "cyclonic separators"
N55: PCV system doesn't use them

N54: No Valvetronic system (More complex oiling system)
N55: Valvetronic system, with simplified oiling system

N54: Intake valve size: 31.4mm, Lift is 9.7mm max
N55: Intake valve size: 32.0mm, Lift is 9.9mm max

(exhaust valve size/lift values are the same)

N54: Less span on intake/exhaust duration
N55: more span on intake/exhaust duration

N54: VANOS units are heavier (possibly not Al), and slower adjusting
N55: VANOS units are lighter (Made from Al), faster adjusting, simplified oiling

N54: BMW Piezo high pressure (HPI) multi-hole fuel injectors
N55: Bosch solenoid-valve fuel injectors (HDE) multi-hole are used

N54 & N55: Use same HPFP, Pressure sensor & fuel rail

N54: Dual mass (heavier) vibration dampener for crank
N55: Single mass (lighter) vibration dampener for crank

N54: Diverter valves are operated pneumatically
N55: Diverter valve is operated electronically

N54: Four catalytic converters are used
N55: two catalytic converters are used (two "bricks" are inside the single canister)

N55: PCM "DME" is mounted directly to intake manifold, and is cooled by intake air.

N55 has newer ignition coils.

N55 has newer oil pressure sensor that reads absolute pressure (N54 reads relative pressure)

N55 has a newer more accurate O2 sensor

N55 uses a Mass airflow sensor, N54 does not.

[Aries932]

This is the other thing I wanted to bring over that I thought was interesting. Now granted there are a lot of variables, but this is the closest thing to a tune on tune test I could find.

Below are two dyno charts






Chart 1
2008 E90 335i
AMS Intercooler
AMS Catback Exhaust
VK Downpipes
CP-E Charge pipe/Tial BOV
DCI
3 Runs with PROcede v4 Autotuning 100 octane (19psi)
3 Runs with JB3 dynos on Map 7 on Pump Gas. (15-16psi)


Chart 2
N55 135 w/7DTC
91oct
Vishnu Procede v5
Vishnu DP
Vishnu Large charge pipe
Cat-back
No Intercooler
No Cat back exhaust

Now these cars are the closest I could find to similar mods. Obviously the N54 running 100 octane is going to make a huge difference. Please note that the N55 is running less than 15psi.





Chart 1
3.0 - 220
3.5 - 250
4.0 - 280
4.5 - 320
5.0 - 360
5.5 - 380
6.0 - 380

Chart 2
3.0 - 230 (+10)
3.5 - 260 (+10)
4.0 - 295 (+15)
4.5 - 350 (+30)
5.0 - 360 (+0)
5.5 - 355 (-25)
6.0 - 340 (-40)

So even though the JB3 is running more more psi and pulling 25 more peak HP..throughout the RPM band the N55 holds its ground all the way until the last 1000 RPM's. I just think that is worth noting. Now put that together with the DCT.

[tscdennab]

Originally Posted by Aries932

N54: Crank is forged, weighs approx 23.3Kg
N55: Crank is case, weighs approx 20.3Kg

^Wow, great info above !

So you mean that the N55 crank is cast (what does "case" mean ?) and not forged ?

[Aries932]

Originally Posted by tscdennab

^Wow, great info above !

So you mean that the N55 crank is cast (what does "case" mean ?) and not forged ?

Yes the crank in the N55 is not forged. If you are looking to do an upgraded turbo application...you want to buy a N54.

Oh and it was not me that put that together...notice the Thanks Dackel part.