[Gio72]

Originally Posted by Jim Pearce

Even directly from BMW this claim is hard to believe. In essence, the whole graph has been extended 500 rpm to the right of anything I've seen before from a third party dyno test of the N55 in any tune. If this bears out the MPPK is a remarkable tune. As for my car, it arrives later this week - and even then I won't be pulling 6000 rpm anytime soon.

Pull, pull over 6000 to 7000 with no doubts, believe me (after a good brake-in period of course)
That's a video of my 435i MPPK:

Even if it's only a video, do you notice a drop after 6000???
Excuse me, but did you watch at the video of the test of M235i I posted before? What did they're day about N55 behaviour at high revs? Maybe my english is very poor and I missunderstood something... But it's just one of lots of these tests and the conclusion is always the same.

[BimmerBoomer]

He makes a lot of mistakes. At any rate, the M235i dyno data I've seen shows the power falling from the peak at around 6000 rpm to 7000 rpm - about the same as all of the N54 and N55 data I've seen to date. http://www.2addicts.com/forums/showthread.php?t=961724 Generally, tuning a turbocharged engine tends to move the horsepower curve up - not to the right.

[Gio72]

Generally... We're talking of the last version of N55, not in generally of a turbocharged engine
The tester makes mistakes in his opinion, BMW makes mistakes in the curves claimed... Ok, I stop here and hope to come back soon to track to enjoy again my strange high revs turbocharged engine
Good night, in 6 hours I'll wake up...

[RPM90]

Originally Posted by Jim Pearce

What I know is that BMW claims peak power on the N55 in the F30/32 at 5800 rpm, in the M235i at 5800-6000 rpm. As I recall, peak power with the N54 and Dinan stage 2 was at 5700 rpm. So, 200-300 rpm.

Provided mostly for the poster known as Gio.

M235i peak HP BMW rated at 5800 - 6000 rpm.
Peak torque is a great spread at 1400 - 4500 rpm.
Very impressive these directed injected modern turbo's.

335i peak HP rated at the same 5800 - 6000 rpm.
Peak torque spread at 1300 - 5000 rpm.

So it looks like the M235i's greater torque number comes in a bit later and dies off a bit quicker compared to the 335i's tune.

Early N54 shows peak HP at 5800 rpm.
Peak torque spread at 1300 -5000 rpm, similar to the N55 in the 335i.
BMW also claimed that the twin scroll tube N55 achieved peak torque
at lower RPM.

Still, both 3.0 turbo engines, and their stock tune variants, are fantastic.
I had an N54 135i and it rocked.
The N55 in my 335i Msport is also excellent.
Interestingly, my N55 combined with the 8spd AT feels stronger than the N54 with MT in my 135i. But's that's due to the ZF 8spd AT.

Digress:
I'm not doing a tune on my 335i, because I've become disillusioned by the cars overall softness, and because my ZF AT sucks in manual mode.
The first 2-3 shifts are jerky like a badly done MT shift.
There's a bit of hesitation on the shift and then it engages and it make my head bobble. This is in manual mode sport or normal/comfort.
In full auto mode the shifts are like butter.
Manual mode downshifts also suck once I get to 4th on down.

I stopped using the manual mode cause my trans sucks.
The dealer is full of crap telling me it's normal. Ever other 8spd AT I've driven in 320i's, 328i's, and other 335i's the manual shift mode is perfect and excellent.

I can't wait to get out of this 335i and likely get the 2 series.
Not sure if I want the M235i or 228i with Msport yet.
Haven't driven them yet, but I'm really hoping they are more like my 135i and less like my 335i Msport.

[RPM90]

Originally Posted by Alpine435i

Gio, I don't think you understand what "pulling to 7000 RPM" entails. Yes, the engine will rev to 7000 RPM and it's still producing some level of output at that RPM, but the engine is well past its efficiency range. These engine/turbo combinations run out of breath in the top half of the RPM range and it's very obvious if you look at a dyno.

The average N55 torque and horsepower curve looks something like this, be it stock or lightly modded:


As you can see, peak power is made between 4500-5500 RPM then it tapers off. It's far from ideal, and no one will consider this a powerband which "pulls to 7000 RPM." Even the BMW 435i development car, one of the most powerful F-Series N55 cars, made peak power around 5500 RPM then declined to redline. Although it's still delivering torque to the wheels and the car is accelerating to redline, giving the feeling that you mention, it's not "pulling."

An ideal horsepower curve peaks at redline because an ideal torque curve is flat and horsepower is merely a derivative of torque. For example, something like this...

Great numbers!

Yes, it is true that most modern turbo engines will quick spooling small turbo's give big torque at low to medium rpm and taper off quickly well before red line.

The dyno you're showing exaggerates that drop, because as you boost the psi from these little turbo's they can perform in the low mid to mid rpm, but the drop is even more exaggerated because of the big increase in output.
These small turbo's simply run out of breath at higher rpm.

In a stock N55 the drop is not as severe, but they too run out of torque production well before red line.

[RPM90]

Originally Posted by nicknaz

Maybe it is because you were using a Dinan tune that tapers boost at high RPM, instead of say the cobb 93 octane tune that targets more boost at high rpm

Different tunes may seek a different power curve so that there is less of a peak in a limited band to get lower peak power yet try to spread the power across a greater rev range.

But, the limiting factor is still the small turbo.
It can only give so much, and it can't give more at higher rpm cause it can't flow the air volume needed.

You can't have it all with a small turbo, just as you can't have big low rpm torque with a larger, greater CFM turbo.

BMW switched to a single twin-scroll turbo because that type can give the same power at low rpm while also providing good air flow at higher rpm.
With the TS turbo BMW was able to remove the need for 2 turbo's and all associated plumbing while still having the 3.0 produce the same power numbers.
Still, the TS is also a small turbo that can only flow so much.
It has a slightly broader power curve, but not much.

A sequential set up with a small turbo for low rpm that transitions to a larger turbo at high rpm can give you that.
Or, a variable vane turbo like Porsche uses that can flow like a small turbo at lower rpm and a larger turbo at higher rpm. That's great turbo tech, but costly.

What BMW has created with the TS turbo is still pretty darn impressive.

[RPM90]

Originally Posted by Gio72

Pull, pull over 6000 to 7000 with no doubts, believe me (after a good brake-in period of course)
That's a video of my 435i MPPK:
Even if it's only a video, do you notice a drop after 6000???
Excuse me, but did you watch at the video of the test of M235i I posted before? What did they're day about N55 behaviour at high revs? Maybe my english is very poor and I missunderstood something... But it's just one of lots of these tests and the conclusion is always the same.

Gio, I've had an N54 and now N55.
Stock, neither engine pulls with the same level of force all the way to red line.

Either engine stock will easily and graciously pull to red line and there will still be accelerative force. HP is still pretty decent up to red line.
But, peak torque drops off considerably well before red line.
As the torque drops it's not like the power falls off of a cliff, but the pull is not as strong and you really feel it by around 6000rpm.

I can easily feel it just like most drivers of these engines can.
If you are unconvinced of this, then take a look at real dyno's of stock engines, and you'll see the big drop off in torque well before red line.

As for standing start runs, like a drag race, where to shift for best acceleration is discussed quite a bit in this forum.
Do a search for those topics to see who shifts when and what times and speeds they achieve.

BMW obviously feels that going to near red line is the optimal shift point for fastest acceleration with the auto trans, as evidenced by where the trans shifts on hard accel runs.
Some AT and MT drivers don't agree.
But, once you put a different tune on the engine the torque curve get's peakier and that may necessitate an earlier shift.
Check the threads for more info on that.

[Falafel Combo]

Do you guys seriously not have anything better to do?

[RPM90]

Originally Posted by alpinweiss 335i

Do you guys seriously not have anything better to do?

No actually.

Seems you don't either as you're here, and took the time to post.

This is an auto forum, and we are discussing auto related content.
What should we be doing and posting, how to crochet?

[Falafel Combo]

Originally Posted by RPM90

No actually.

Seems you don't either as you're here, and took the time to post.

This is an auto forum, and we are discussing auto related content.
What should we be doing and posting, how to crochet?

Lol! Not what I meant funny man. I meant that you guys have been going back and forth about this all day!

[Gio72]

Originally Posted by RPM90

Gio, I've had an N54 and now N55.
Stock, neither engine pulls with the same level of force all the way to red line.

Either engine stock will easily and graciously pull to red line and there will still be accelerative force. HP is still pretty decent up to red line.
But, peak torque drops off considerably well before red line.
As the torque drops it's not like the power falls off of a cliff, but the pull is not as strong and you really feel it by around 6000rpm.

I can easily feel it just like most drivers of these engines can.
If you are unconvinced of this, then take a look at real dyno's of stock engines, and you'll see the big drop off in torque well before red line.

As for standing start runs, like a drag race, where to shift for best acceleration is discussed quite a bit in this forum.
Do a search for those topics to see who shifts when and what times and speeds they achieve.

BMW obviously feels that going to near red line is the optimal shift point for fastest acceleration with the auto trans, as evidenced by where the trans shifts on hard accel runs.
Some AT and MT drivers don't agree.
But, once you put a different tune on the engine the torque curve get's peakier and that may necessitate an earlier shift.
Check the threads for more info on that.

Good morning!
My old N54 was far from pulling till the red line, even if on dynojet it reached maximu power around 6100rpm, so it was worth to hold the gear till 6300/6400rpm, not more.
My N55 MPPK is different, because in the range 5000-7000 it seems a normally aspired engine. Everybody in my Italian forum noticed this attitude. I don't know, but maybe it's due to different fuel we use... If you see again the claimed official charts, the peak in power is mantained up to 6500rpm, with a low drop to 7000: that's is exactly the behaviour of my N55
Have a nice day

[Maddict3]

Originally Posted by spmd11

Ok, so we just bought an M235. What is with this engine in the little beast?This car is absolutely amazing for a non-M car.

We are ordering a second car ED, and I'm trying to decide between another M235 and a 335. Kinda like the 335 for practicality, but don't have to have the four doors..just would be nice. But I want another fun car (5 drivers now in a family of 6). If I got the 335, I would order the MPE and PPK.

My question is this. The M235 power delivery is just ridiculous. It just pulls and pulls all the way to redline. We have owned several cars with the N54 and N55 since 2007. None of those cars, including the two 335is's that we owned could pull like the M235 up to redline. Is the PPK 335 N55 like this? Or is the M235 engine altogether different than the other N55 equipped cars?

PPK 335 owners?

If you haven't driven the M235, you owe yourself a test drive. This is the most exciting car from BMW in a long, long time. It's the real deal.

nope M3/M4 is the most exciting car coming.

Drove a M235i at it was great very similar in speed to my 335is.

[spmd11]

Originally Posted by Maddict3

[/B]

nope M3/M4 is the most exciting car coming.

Drove a M235i at it was great very similar in speed to my 335is.

I stand corrected.

[tdizzle]

The recent update to the n55 seems to make it hold power up top better and that's the version the m235 has. The dyno from the tuner is off the "older" n55 which died up top as noted.

Look up the tunes of the n55 with electric waste gate and they're better looking than the older ones in comparison. It's just that they're still being developed but BMS 435 looks to put down about 15whp more than a similarly modified older version and they're not done ironing out the kinks yet. I think they hit 410whp on their first real try with more room to go and the dyno held power better up top.

BMW increased the size of the turbo outlet a bit if I recall.

This would explain why the newer ppk was released with a higher output than the original.

I just wish I would've waited a couple years for the '14... Or just held out for the new m4.

[alienranch]

Now that we're off topic anyway, anyone have 0-60 figures for N55 335i with a BMS JB4? I believe I'm putting down about 50 hp additional to the wheels. Should be quicker than the MPPK but not sure how much. This thing feels like it pulls close to what my C6 Vette did. Simply amazing.

[fecurtis]

Originally Posted by spmd11

My question is this. The M235 power delivery is just ridiculous. It just pulls and pulls all the way to redline. We have owned several cars with the N54 and N55 since 2007. None of those cars, including the two 335is's that we owned could pull like the M235 up to redline. Is the PPK 335 N55 like this? Or is the M235 engine altogether different than the other N55 equipped cars?

PPK 335 owners?

If you haven't driven the M235, you owe yourself a test drive. This is the most exciting car from BMW in a long, long time. It's the real deal.

Oh yes, it pulls extremely hard. And if you're already moving and you hit the WOT to pass someone, the car takes off like a rocket.

I am dying to get behind the wheel of an M235i though.