[atomic837]

Hey everyone. I'm a new M2 owner that is on the cusp of completing the 1200 mile break-in service. I've been a member on these forums since 2008, when I purchased a 2009 135i, but I haven't really been an active poster.

Anyway, as I still own and drive my 135i, I've been compelled to talk about my observations between these two platforms. Although new model platforms and 9 years separate them, there are still more than the fair share of similarities.

One of the differences I think I'm noticing is in throttle response. The 135i had a twin turbo set up on its N54 engine. While certainly not razor sharp like a NA motor, the throttle response was surprisingly lively, with very slight delay between pedal and full boost. This always made everyday driving a snap.

The M2's N55 twin-scroll single turbo arrangement seems to add a hair more lag in daily driving. Where the N54 might have had a 1/2 second delay in power delivery, the M2 feels more like 3/4 to 1 second. This is just a rough estimate.

Because of this difference, driving the two cars back to back, there's a perception that the 135i feels, dare I say it, a little bit faster in low RPM driving.

Just to be clear, I'm not saying that there is no pedal response. The engine responds immediately, but the sensation of proper boost takes those extra fractions of a second. Driving in Sport+ helps only slightly.


Am I crazy to think this? Does the break in service or a new software update remedy this at all? Has anyone here had the opportunity to compare these two engines for this characteristic? Is the twin turbo set up superior to the twin scroll, or is this just a difference between the functionality of the N54 vs N55?

[MZWIE]

No comparison. My 2008 135 was always lagging. Could never correct it no matter what I tried.

My M2 in SPORT+ is extremely responsive.

[atomic837]

Did you notice any difference after break-in, or a subsequent software update?

[MerlinPurple]

OP, I felt the same when I first got the M2.... coming from the S54 the lag was really noticeable in comfort. However, post run-in and 3k mi later the lag has diminished.

Get the RI + a few good miles done and you should see an improvement

[auf Deutsch]

Sport cat DP, problem solved

[PackPride85]

The only "lag" I get is between shifting w/ the manual. You really have to rev it nearly to red line if you want immediate power on the next shift. A little annoying but not a deal breaker.

[ddk632]

I am also a new M2 owner, and I expected there to be lag and there is, in my experience from driving already over 3000 miles. My car was broken in already with 39xx miles on it when I took delivery.

When accelerating hard and shifting anywhere from 5500 to 6500 rpms or so, there is a noticeable delay of the turbo spooling up and the full power coming in the next gear.

Shifting over 6500 rpms or close to/at redine reduces this delay,.

As another poster already mentioned, a downpipe with sport cat will allow the turbo to spool up faster, and should reduce some of this delay. I have one on order.

[McPurrs]

Are you in sport or sport +? I would think the lag would be less in either than normal..

[atomic837]

I've experimented in all three modes. Sport+ is much more sensitive, but I don't think it truly changes much in regards to turbo lag.

Granted, I'm still pre break-in, so I haven't exactly hammered the car yet, but I do notice a difference just driving around town when compared to my 135i N54.

Will update once break-in is complete this weekend.

[MZWIE]

Comfort mode doesn't count. It feels like an old Rambler. To compare to the N54 you must use SPORT+ (DCT).

What you feel as turbo lag, in the case of DCT, is the slight delay in clutch engagement when starting from a standstill.

Try sequential in first and you will be surprised.....

[quikM2]

I notice the delay, its a turbo and a manual. I'm coming from a supercharged Audi S4 and that was ever so slightly more responsive. But the M2 spools so low once you get into it in sport+ especially it really becomes irrelevant.

[mm2862]

No complaints here. Very responsive.

[her02k]

No noticable lag here

[mercedesc63]

Originally Posted by atomic837

Hey everyone. I'm a new M2 owner that is on the cusp of completing the 1200 mile break-in service. I've been a member on these forums since 2008, when I purchased a 2009 135i, but I haven't really been an active poster.

Anyway, as I still own and drive my 135i, I've been compelled to talk about my observations between these two platforms. Although new model platforms and 9 years separate them, there are still more than the fair share of similarities.

One of the differences I think I'm noticing is in throttle response. The 135i had a twin turbo set up on its N54 engine. While certainly not razor sharp like a NA motor, the throttle response was surprisingly lively, with very slight delay between pedal and full boost. This always made everyday driving a snap.

The M2's N55 twin-scroll single turbo arrangement seems to add a hair more lag in daily driving. Where the N54 might have had a 1/2 second delay in power delivery, the M2 feels more like 3/4 to 1 second. This is just a rough estimate.

Because of this difference, driving the two cars back to back, there's a perception that the 135i feels, dare I say it, a little bit faster in low RPM driving.

Just to be clear, I'm not saying that there is no pedal response. The engine responds immediately, but the sensation of proper boost takes those extra fractions of a second. Driving in Sport+ helps only slightly.


Am I crazy to think this? Does the break in service or a new software update remedy this at all? Has anyone here had the opportunity to compare these two engines for this characteristic? Is the twin turbo set up superior to the twin scroll, or is this just a difference between the functionality of the N54 vs N55?

I think the Engine in the current M2 was definitely the deal breaker for me. I loved the N54 it was better.

Now that the new M2CS with an S55 is more my speed. The S55 has no turbo lag at all which is impressive.

[jayg80]

Could it be that it's not really lag but that you are a little low down on the tach? I find that although max torque begins at 1450rpm the car doesn't really start to push me into my seat until about 2500rpm.

[chris719]

It seems like the N55 should have less turbo lag than N54 or S55, but who knows. There is so much firmware trickery for emissions and fuel economy reasons these days it is almost impossible to say.

[zFrostyy]

Originally Posted by mercedesc63

I think the Engine in the current M2 was definitely the deal breaker for me. I loved the N54 it was better.

Now that the new M2CS with an S55 is more my speed. The S55 has no turbo lag at all which is impressive.

The n54 engine is better because of electronic throttle calibration?

To OP, the throttle response will change as you drive it more with drivelogic. It takes more than 1000 miles for it to learn how you drive and what throttle response you want.

Use different modes depending on if you're driving sporty or not, comfort, sport, etc. and it will tune the throttle response to how you normally drive in those modes. Comfort will always be slower paced if you only use it when you're in traffic or tired/don't want to think while driving.

Sport/Sport+ will always be snappier and more responsive if you use them while moving the throttle around a lot, aka driving sporty.

[mercedesc63]

Originally Posted by zFrostyy

The n54 engine is better because of electronic throttle calibration?

To OP, the throttle response will change as you drive it more with drivelogic. It takes more than 1000 miles for it to learn how you drive and what throttle response you want.

Use different modes depending on if you're driving sporty or not, comfort, sport, etc. and it will tune the throttle response to how you normally drive in those modes. Comfort will always be slower paced if you only use it when you're in traffic or tired/don't want to think while driving.

Sport/Sport+ will always be snappier and more responsive if you use them while moving the throttle around a lot, aka driving sporty.

I think the N54 is better because it was first. It was light years ahead of the competition in terms of speed upon its release in 07'. It is twin turbo, has regular throttle setup (n55 has no throttle bodies valvetronic) and, 7psi stock boost (n55=10psi boost for same hp). It is just a different engine to compared to the N55 which in my opinion wasn't the right replacement.

I am more of a 1M guy than an M2 guy.

[BruceM]

I don't know what the N54 twin turbo sounds like, but IMHO the S55 twin turbo sounds....bad. How do the two compare in sound?

Not that sound is everything. But it is something.

[mmmpassion]

Similar topic:
http://f87.bimmerpost.com/forums/sho....php?t=1322317

[filet.M2c]

Originally Posted by BruceM

I don't know what the N54 twin turbo sounds like, but IMHO the S55 twin turbo sounds....bad. How do the two compare in sound?

Not that sound is everything. But it is something.

For reference, here was my n54 135i with full exhaust.... oh and the horrible wastegate rattle

[pruettfan]

I added the Dinantronics Sport tuner and it really eliminates that slight mid range lag, based on their data it doesn't add a whole lot of HP but it does add some nice torque which can really be felt without impacting driveability. I would say its well worth the 300 bucks, works off an iPhone app so you can choose to run stock or several other profiles which are just additional boost.