[cap_freez]

Hey guys,

just wondering. I see a lot of negative comments on the N55 that will be powering the new 135 and 335 cars. Why is that?

I understand people who want to tune their cars will have to wait longer for new ecu updates, but isn't this engine supposed to be as powerful while improving consumption? Also maybe all the HPFP issues will at last be fixed.

Anyone care to enlighten me on why no one seems to be looking forward to this update?

[galahad05]

Stock for stock, the new n55 has a very slight edge over the n54 it replaces. It is also supposed to get a little better gas mileage while doing so. If you don't plan/want to ever go beyond stock, then the n55 is slightly better than the n54.



For tunability, however, things don't look as good. It's a single turbocharger with a very low spool-up RPM. This limits just how big this turbo can be: Even with the twin scrolls, this means that the turbo (which looks to be bigger than one of the n54 turbos it replaces, but not bigger than both put together) can't compress as much air as the two turbochargers it replaces, at the limit.

Or, to put it another way, I'm told (guesstimate by someone who should know™) that the stock n54 is a detuned 400 HP motor, while the stock n55 is a less-detuned 360 HP motor.

[E92-Lighting]

there is no hate towards N55, just a newer built engine

[Jonny550]

Originally Posted by galahad05

Stock for stock, the new n55 has a very slight edge over the n54 it replaces. It is also supposed to get a little better gas mileage while doing so. If you don't plan/want to ever go beyond stock, then the n55 is slightly better than the n54.



For tunability, however, things don't look as good. It's a single turbocharger with a very low spool-up RPM. This limits just how big this turbo can be: Even with the twin scrolls, this means that the turbo (which looks to be bigger than one of the n54 turbos it replaces, but not bigger than both put together) can't compress as much air as the two turbochargers it replaces, at the limit.

Or, to put it another way, I'm told (guesstimate by someone who should know™) that the stock n54 is a detuned 400 HP motor, while the stock n55 is a less-detuned 360 HP motor.

+1

[JakeN5]

No hate for N55 here. I can live with less-detuned 360HP. That's more HP than I can handle or need, and as a matter of fact, more HP than 98% of this board's members can handle. some people immediately are gonna repudiate this post by blah blah blah what they think they can do after reading it. I'm gonna get the N55 when the time comes to switch cars.

[Javier]

i guess two turbos just sounds better than one

[Ilma]

Originally Posted by Javier

i guess two turbos just sounds better than one

Not when you have to replace them!

[Bluechipper]

Just like when the F30 comes out.

There will be haters.

Until they buy and then its the greatest thing on the planet.

[Willizm]

I like having new things come along. Makes the industry better. Problem with the N55 from my standpoint is that it's replacing all the engines in the 335i and 135i while the more sports minded 335is gets to keep the N54. That fact makes me feel that BMW isn't moving forward with the performance of the N55 and is instead nurfing the platform. If the 335is had a higher output N55 then I would have a completely different look at that engine.

[vase330]

You have to look at it from BMW view point. More horse power gets them more sales but only to a point. However the N54 in all its HP capability glory has the disadvantage that it consumes more and pollutes more. Have you heard of fleet average economy? Yeah, that hurts their numbers more than the N55, which is cleaner and more economical. It matters because there is a fee associated with those numbers, and the worse they are, the more you are penalized as a manufacturer. So say you get two new customers because of the N54 is carried over, but now you have to pay an extra $1 million in fees compared to N55 which would bring your numbers down across your fleet. Are the two customers worth it to you? No! BMW is a business, which means the bean counters absolutely have the biggest say in the product line no matter what BMW says about Ultimate this and that. BTW that's just marketing.

So absolutely to be realistic N55 > N54. They tried to have their cake and eat it too, keeping the N54 for the more sports oriented "IS" so they give to the enthusiast crowd what they prefer. They also are not stupid, they know some people will buy a car just because the motor is mod-friendly . Look at all the STI, EVO crowd that jumped ship. BMW knows that, and I am sure its in their calculations somehow. Of course they have also extrapolated warranty claims, and how many warranties they must absolutely void to make the business case for that too. Nothing is left to chance, you can believe that. Everything is all about opportunity costs vs reward. As ultimate driving whatever as you might think they are, if they could make a completely neutered 120 HP un-moddable car that sells like crazy, you better believe that is what they'd do. In the end is all about the bottom-line. That is why I laugh when people complain about M-division SUVs and none inline engines. If they can sell it, they will make it, "M Philosophy" be damned.

[JoeyFiasco]

Originally Posted by vase330

You have to look at it from BMW view point. More horse power gets them more sales but only to a point. However the N54 in all its HP capability glory has the disadvantage that it consumes more and pollutes more. Have you heard of fleet average economy? Yeah, that hurts their numbers more than the N55, which is cleaner and more economical. It matters because there is a fee associated with those numbers, and the worse they are, the more you are penalized as a manufacturer. So say you get two new customers because of the N54 is carried over, but now you have to pay an extra $1 million in fees compared to N55 which would bring your numbers down across your fleet. Are the two customers worth it to you? No! BMW is a business, which means the bean counters absolutely have the biggest say in the product line no matter what BMW says about Ultimate this and that. BTW that's just marketing.

So absolutely to be realistic N55 > N54. They tried to have their cake and eat it too, keeping the N54 for the more sports oriented "IS" so they give to the enthusiast crowd what they prefer. They also are not stupid, they know some people will buy a car just because the motor is mod-friendly . Look at all the STI, EVO crowd that jumped ship. BMW knows that, and I am sure its in their calculations somehow. Of course they have also extrapolated warranty claims, and how many warranties they must absolutely void to make the business case for that too. Nothing is left to chance, you can believe that. Everything is all about opportunity costs vs reward. As ultimate driving whatever as you might think they are, if they could make a completely neutered 120 HP un-moddable car that sells like crazy, you better believe that is what they'd do. In the end is all about the bottom-line. That is why I laugh when people complain about M-division SUVs and none inline engines. If they can sell it, they will make it, "M Philosophy" be damned.

true, from an enthusiast (and I use the term loosely) I thought "wtf is the point of this?" but it is a business..

[hun77777]

once there are more aftermarket tunes and parts available, people will love n55 equally as n54. they just are not sure about this n55 engine yet since there's not so much information available from tuner side...

[Spydeputy]

I'll just wait to hear f/ the tuners, and see there take on it. stock N54 vs. stock N55. is an easy compare. Tune N54 vs Tune N55. will be a wait and see.

[cotmfk]

Personally, it's a wait and see attitude on the N55 for me. 330-360 whp ish from the N54 for little money is pretty awesome.

[ArmyBimmerDude]

People love criticizing updated versions of their cars because they dislike the idea that their model is outdated or obsolete. It's like the Pre-LCI E90 guys hating on the LCI model. They know their cars are ugly, but refuse to admit that and bash to make themselves feel better. Once there are tunes out for the N55, we'll get a better idea of its potential.

[Bagelfast]

^ Even tho i do agree, i think most people who arent the first to jump on the N55 are most guys who want power.

The N55 will have more anti-tuning stuff to it software and DME wise, heck even the DME is on the engine now lol. But the new valventronic it has, will be somewhat of a limiter in terms of what can be done and power/such.

Another aspect wil be what the turbo can push on the N55, the N54 has responded VERY well to just tunes and bolt on's, BMW came late into the game trying to stop people from tuning it, via software updates (29.2+) and hardware changes (MSD81), but didnt stop the fact the tuners went around this easily in about a months time because this was a after thought from bmw.

This time around i am sure they will not let that happen and are ready to throw some nice curve balls at the tuners. Nice it will be able to be tuned, i am 100% on that no doubt.

But the power that will be able to extract i am pretty certain wont be as much as the N54.

Being 3-4 years into R&D for tuning the N54 platform, its another win for guys who want more power.

[Graystone]

Originally Posted by galahad05

Stock for stock, the new n55 has a very slight edge over the n54 it replaces. It is also supposed to get a little better gas mileage while doing so. If you don't plan/want to ever go beyond stock, then the n55 is slightly better than the n54.



For tunability, however, things don't look as good. It's a single turbocharger with a very low spool-up RPM. This limits just how big this turbo can be: Even with the twin scrolls, this means that the turbo (which looks to be bigger than one of the n54 turbos it replaces, but not bigger than both put together) can't compress as much air as the two turbochargers it replaces, at the limit.

Or, to put it another way, I'm told (guesstimate by someone who should know™) that the stock n54 is a detuned 400 HP motor, while the stock n55 is a less-detuned 360 HP motor.

+1 also

[bdkevoIX]

Originally Posted by galahad05

Stock for stock, the new n55 has a very slight edge over the n54 it replaces. It is also supposed to get a little better gas mileage while doing so. If you don't plan/want to ever go beyond stock, then the n55 is slightly better than the n54.



For tunability, however, things don't look as good. It's a single turbocharger with a very low spool-up RPM. This limits just how big this turbo can be: Even with the twin scrolls, this means that the turbo (which looks to be bigger than one of the n54 turbos it replaces, but not bigger than both put together) can't compress as much air as the two turbochargers it replaces, at the limit.

Or, to put it another way, I'm told (guesstimate by someone who should know™) that the stock n54 is a detuned 400 HP motor, while the stock n55 is a less-detuned 360 HP motor.

It's funny how people think they came up with a "reasonable" conclusion without knowing the actual flow rate of the new turbo. Twin scroll makes a world of difference in spool, and the effect is even more pronounced in large displacement engines.

Just wait and see.

[ragingclue]

I'm sure it'll be easier to fab a single turbo replacement for the N55 than it is for the N54.

[cn555ic]

Originally Posted by ArmyBimmerDude

People love criticizing updated versions of their cars because they dislike the idea that their model is outdated or obsolete. It's like the Pre-LCI E90 guys hating on the LCI model. They know their cars are ugly, but refuse to admit that and bash to make themselves feel better. Once there are tunes out for the N55, we'll get a better idea of its potential.

I dont own a E90, but I will tell you the new LCI models are much better looking especially since the kidney grills are one piece like the E92...They looked horrible with the two peice kidney setup! I don't know much about the N55, but I am sure there will be a tune soon for it, but the problem is the motor is already detuned down, so having a tune will bring the performance to what is considered a stock N54 engine!!! lol
But this is my OPINION

[Slidewayz]

I'm sure the tuners will find a way to tune the N55.

It might be easier to upgrade a single turbo than the munchkin twins.

So, who knows, maybe the N55 has more upside potential than the N54.

[cstavaru]

I'm biased. You can skip this post

I really don't know if the N55 is good or bad. Only one hint from the new N55-based 5-series review: the engine doesn't have quite the low-end of the N54. I didn't find any other comparisons. We will have to wait a few weeks.

Worth noting is that the N55 turbine is twin-scroll, so its quite complicated in design, and also includes other engine parts in the turbine housing like the wastegate. An upgrade is not easy to do, if you ask me. And I do think that turbo upgrades are the upgrades which ruin the intended engine characteristics.

The beauty of the N54 lies in the fact that you can squeeze alot of power from it with very simple and cheap modifications: With $2000 (JB3 pinout + intercooler + downpipes + DCI) you can reach about 400whp up from the original ~270whp. That's a 50% increase in power...

N55 will surely be tunable, but I think at least 2 years will have to pass until the first non-flash tunes. Flashes will probably be available sooner, but I am not sure...maybe BMW really became paranoid this time.