[justinnum1]

N54>N55

i really wish the f30 had the N54.

[DerekS]

Originally Posted by justinnum1

i just think the N54 was stronger.

This is not indicated by most road tests of the N55. If you need more power, maybe you should consider the added horsepower offered by the M Performance package that will be available in a few months time.

In any case, the N55 is a much more fuel efficient engine than the N54.

[grimlock]

Originally Posted by claykin

I've been told my BMW mechanics to think of the N55 as a cost reduced version of the N54. BMW simplified the design, cut out some of the high end components (i.e. piezo fuel injectors, dual independent turbos) and traded off raw performance for ability to better control fuel consumption.

N55 still uses HPFP, but design has been improved. N54's with latest HPFP should no longer experience high failure rates. My E90 MSport is still on its original fuel pump. The 2010 DME reprogram is said to address this issue.

Yes, the N55 is a cheap, fuel efficient replacement for the N54, which should be coming out of the factory for 350-390HP applications. The N55 is well suited for the 300-350HP range. BMW is so cheap.
Which is why I avoid the 35i- engines in the F30 and F10.. they are just trying to wring out as much profit as they can from unknowledgeable consumers.
The N54 when it came out on the e90 was a good buy, severely underrated and lots of potential. The current N55s barely squeak by in my book.
The gap with the f30 M3 should be much larger, hence waiting for the M3 a better idea especially since the current f30 N55 should be updated quickly.

[SamGh]

Originally Posted by verbs

There have been multiple dyno testings of each car, the N54 just makes more horsepower than the N55, period. There are no ifs ands or butts about it. N54 is more underrated if you would from the factory than the N55.

That said, not having to deal with high pressure fuel pump issues and the aforementioned gas mileage gains are a plus from a convenience perspective. Just wish the car pulled harder up top, at least as much so as the N54, which I even felt fell flat on its face up top.

I hope you are at least a tuner to be so sure about your comment, but I give you full benefit of doubt....
On the other hand, not having to worry about your engine to fail is not convenience,it is reliability and these things all Matter for a stock engine. Power is not the only thing you expect from a 50-60k car. I don't drive a car to race every day, though, some kids might...

[verbs]

Originally Posted by shahramghs

I hope you are at least a tuner to be so sure about your comment, but I give you full benefit of doubt....
On the other hand, not having to worry about your engine to fail is not convenience,it is reliability and these things all Matter for a stock engine. Power is not the only thing you expect from a 50-60k car. I don't drive a car to race every day, though, some kids might...

You don't have to be a dyno tuner to know reality. Here's one example of many....if you do enough research it's out there.

http://www.automobilemag.com/reviews...5is_dyno_test/

[snowghost]

Originally Posted by CheeseJaguar

Configurator says... about the same as a base model M3.

$75,000?

[RPM90]

Originally Posted by claykin

I've been told my BMW mechanics to think of the N55 as a cost reduced version of the N54. BMW simplified the design, cut out some of the high end components (i.e. piezo fuel injectors, dual independent turbos) and traded off raw performance for ability to better control fuel consumption.

N55 still uses HPFP, but design has been improved. N54's with latest HPFP should no longer experience high failure rates. My E90 MSport is still on its original fuel pump. The 2010 DME reprogram is said to address this issue.

The N54 was/is one heck of an engine. I had one in my 135i.
Look at enough dyno's of early N54's, later N54's, and N55's and you soon see that there is VERY little difference in maximum HP and torque output.
Some will show the N55 producing more torque, some showing the N54 producing more HP.
There appears to be as much variance between N54 engines as there is between N54 and N55 engines.
It's a wash.
Biggest, or at least most noticeable difference, is in throttle response, fuel economy, and emissions, which favor the N55, tuning potential goes to the N54.
I don't see the N54 as having more "raw" performance, it's simply not proven stock for stock.

My 135i N54 was very nice, strong.
In my 335i the N55 in conjunction with the whole different drive line feels stronger and smoother to me, not that the N54 wasn't smooth.
I'm just comparing how the whole car responds to throttle input.
My N54 had awful throttle response, again, mostly due to BMW's tinkering to "correct" things. My 135i started with decent throttle response, and after a software update that was supposed to address long cranks and potential HPFP issues, throttle response was gone.
My 335i's throttle response is excellent. "Comfort" has better response than my 135i did, and "sport" really sharpens it and I really prefer "sport" mode throttle response.

As for the whole "lower cost version", BMW designed the N55 to be more cost effective to build, but that doesn't mean it's a "lower cost", meaning lesser", engine.

Compared to the N54 the N55 has MORE advanced technology, not simplified.
The N55 uses a twin scroll turbo, which is a more advanced turbo design made to operate with greater efficiency across a broader rpm range.
To do that it uses a more advanced manifold that can flow to the lower rpm side of the twin scroll and then to the higher rpm side.

Also the N55 includes valvetronic, which controls valve lift, and it responds quicker to throttle input. With valvetronic the engine doesn't require a throttle plate to control air flow to the cylinders, that's done by VT controlling intake valve openings
Valvetronic is much more advanced technology than the N54's traditional throttle plate and valve control.

The N55 is actually a very modern turbo engine design, being the first BMW engine to couple turbocharging with valvetronic intake control.
With all the modern technology put into the N55 it is more fuel efficient and produces lower emissions compared to the N54.
Does it cost less for BMW to build? BMW say it does.
But that's an advancement, a positive not a negative.

[RPM90]

Originally Posted by grimlock

Yes, the N55 is a cheap, fuel efficient replacement for the N54, which should be coming out of the factory for 350-390HP applications. The N55 is well suited for the 300-350HP range. BMW is so cheap.
Which is why I avoid the 35i- engines in the F30 and F10.. they are just trying to wring out as much profit as they can from unknowledgeable consumers.
The N54 when it came out on the e90 was a good buy, severely underrated and lots of potential. The current N55s barely squeak by in my book.
The gap with the f30 M3 should be much larger, hence waiting for the M3 a better idea especially since the current f30 N55 should be updated quickly.

You want more power, but then you picked the lower power version of your car.

Good luck with your M3 purchase.

BTW, get a new book.

[SamGh]

Originally Posted by RPM90

The N54 was/is one heck of an engine. I had one in my 135i.
Look at enough dyno's of early N54's, later N54's, and N55's and you soon see that there is VERY little difference in maximum HP and torque output.
Some will show the N55 producing more torque, some showing the N54 producing more HP.
There appears to be as much variance between N54 engines as there is between N54 and N55 engines.
It's a wash.
Biggest, or at least most noticeable difference, is in throttle response, fuel economy, and emissions, which favor the N55, tuning potential goes to the N54.
I don't see the N54 as having more "raw" performance, it's simply not proven stock for stock.



My 135i N54 was very nice, strong.
In my 335i the N55 in conjunction with the whole different drive line feels stronger and smoother to me, not that the N54 wasn't smooth.
I'm just comparing how the whole car responds to throttle input.
My N54 had awful throttle response, again, mostly due to BMW's tinkering to "correct" things. My 135i started with decent throttle response, and after a software update that was supposed to address long cranks and potential HPFP issues, throttle response was gone.
My 335i's throttle response is excellent. "Comfort" has better response than my 135i did, and "sport" really sharpens it and I really prefer "sport" mode throttle response.

As for the whole "lower cost version", BMW designed the N55 to be more cost effective to build, but that doesn't mean it's a "lower cost", meaning lesser", engine.

Compared to the N54 the N55 has MORE advanced technology, not simplified.
The N55 uses a twin scroll turbo, which is a more advanced turbo design made to operate with greater efficiency across a broader rpm range.
To do that it uses a more advanced manifold that can flow to the lower rpm side of the twin scroll and then to the higher rpm side.

Also the N55 includes valvetronic, which controls valve lift, and it responds quicker to throttle input. With valvetronic the engine doesn't require a throttle plate to control air flow to the cylinders, that's done by VT controlling intake valve openings
Valvetronic is much more advanced technology than the N54's traditional throttle plate and valve control.

The N55 is actually a very modern turbo engine design, being the first BMW engine to couple turbocharging with valvetronic intake control.
With all the modern technology put into the N55 it is more fuel efficient and produces lower emissions compared to the N54.
Does it cost less for BMW to build? BMW say it does.
But that's an advancement, a positive not a negative.

Well said, and great write up!

[grimlock]

Originally Posted by RPM90

You want more power, but then you picked the lower power version of your car.

Good luck with your M3 purchase.

BTW, get a new book.

N55 does that to people, make them search desperately for reasons to like it, but alas its futile. BMW screwed you over.

[SwnSng]

Originally Posted by RPM90

You want more power, but then you picked the lower power version of your car.

Good luck with your M3 purchase.

BTW, get a new book.

sounds like he's trying to justify his n20 purchase.

[SamS]

One thing is certain... if you have the N54, you will be forever at the mercy of a potentially faulty HPFP. Yes, I realize BMW has extended warranty on them.

The F30 N55, and N55 built after March 2012 have a different/redesigned HPFP than what was available via older N55 and all N54 motors.

[RPM90]

Originally Posted by grimlock

N55 does that to people, make them search desperately for reasons to like it, but alas its futile. BMW screwed you over.

If knowledge and facts are desperation, then you could use a lot more of it.

What I offered is factual information. What you offer sounds like hyperbolic rhetoric.

The N55 is one heck of a good screwing.

[grimlock]

Originally Posted by RPM90

If knowledge and facts are desperation, then you could use a lot more of it.

What I offered is factual information. What you offer sounds like hyperbolic rhetoric.

The N55 is one heck of a good screwing.

I've give you that.
All good.

[Kians313]

shahramghs, thanks for sharing. learning a lot from this thread.
would u mind sharing how much you paid for the car?
I am kinda faced with a choice with a F30 335 MSport or a used E90 M3 comp pkg that are pretty close in price.

[RPM90]

Originally Posted by grimlock

I've give you that.
All good.

[David328M-Sport]

Originally Posted by RPM90

We get some added setting options that non DH 3's don't get.
I use sport mode all the time, every time.
I have mind configured to affect "chassis only". With this setting, throttle response is like comfort mode, trans shifting is also like comfort mode, steering is in sport mode, and suspension is in sport mode.
This gives me a nicely controlled sporty ride, but the trans is butter smooth and shifts shorter and goes to 8th gear even before 55mph.

As well as our cars are appointed here in Australia, my car unfortunately does not have the SPORT mode adjustment in the Settings section of iDrive. It would have been nice to try out Comfort performance (it's how you have it configured - right?) with Sport chassis setting.

I have to take my car in to my dealer for some minor fix ups next week. I will tackle them on the subject but I don't think anything will come of it. However, I wonder if the setting can be switched on through coding. Hmmmmm.

[SamGh]

I was able to get it 500 above invoice, which was a great deal knowing no one had the car I wanted in the area.

[gtabfknkdnme]

laughable how so many people refer to a lowered car in relation to being in high school or 'in my 20s'

other than that. i agree with most of what you said. i love my f30 m sport, but have to say there is just something extra there with my e90 in terms of connectedness to the car and driving feel

[SamGh]

Originally Posted by gtabfknkdnme

laughable how so many people refer to a lowered car in relation to being in high school or 'in my 20s'

other than that. i agree with most of what you said. i love my f30 m sport, but have to say there is just something extra there with my e90 in terms of connectedness to the car and driving feel

I'm actually in late 20s my friend , but for a daily driver, I can't justify lowered car after having two low cars... I have lots to worry about other than how aggressive my cars looks every time I hit the road. What I do worry about more is the god damn front bumper getting scraped when I'm getting in/out lots! I painted that 3 times on my E90... Or every time I'm going fast and all of a sudden some crazy uneven surface/streets sends my car out of my control... Yup, I'm a bit of a crazy driver and I wish I was living in a place where I didn't have to worry about the surface, then I would slam the hell out of my car.

[theriz]

-Electric steering is AWESOME. I like how I don't have to wrestle with the steering wheel in low speeds.

lol.........