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      03-29-2020, 12:10 AM   #45
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Here is 2nd to 3rd to 4th log from earlier in the week when I was first testing a new map from proTUNING Freaks. At this point I was shifting at my normal speed of about 1.4 seconds. Same map as my previous post, the only difference being shift speed: https://www.bootmod3.net/log?id=5e7a...0b43508e6fe7fd


This time, the waste gate doesn't close fully for some period after I'm back on the pedal.

In the log shown above, the delay between pedal going to 100% and waste gate going to 100% is 0.8 seconds for the 2nd to 3rd shift, and 0.7 in the 3rd to 4th shift. The duration between pedal going to 0% for the start of the shift and the waste gate going to 100% is 1.8 seconds for both shifts.

Interestingly, I've gone through all 16 logs that I took with this latest map, and the duration between first lifting the pedal to make the shift and the waste gate going back into controlling boost (which usually means closing) is consistently ~1.8 seconds!
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      03-29-2020, 12:26 AM   #46
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Here is a log showing quick (< 0.7s) shifts from 2nd to 3rd to 4th. Again, same map, only difference is shift speed: https://www.bootmod3.net/log?id=5e7a...0b43508e6fe39e


This time the delay between pedal at 100% and waste gate going above 80% is 1.1 seconds in both cases - longer than when I shifted slower. The duration between pedal going to 0% for the start of the shift and the waste gate going above 80% is 1.7 seconds

In this case, the waste gate never goes to 100% in either shift because boost is already rising fast enough at the point where the waste gate starts to behave normally again. There is a visible bump in the WGDC trace though, which shows that something is going on.

Finally, a log here that shows no waste gate bump at all - the effect is totally masked, because the shift was fast enough and the revs high enough that boost didn't drop enough for the wastage to need to be closed by the time it was operating normally again. You still see the bump on the 3rd to 4th shift, but not at all on the 2nd to 3rd: https://www.bootmod3.net/log?id=5e7a...0b43508e6fe3b4

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      03-29-2020, 12:36 AM   #47
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What does all of this mean for performance though...

Comparing the logs from the >2.0 seconds shifts to the ~1.4 second shifts and the < 0.7 second shifts, the speed at which boost rises is quite different.

In the slow shift log, boost has fallen to zero, there is even a vacuum at the MAP sensor, but the waste gate closes fully and boost builds from 0 to meet the target in just 1.4 seconds. In the quicker shift log, the boost build is the same at 1.4 seconds, but boost wasn't at zero... it started from 3.3 psi; a slower boost build with a much faster shift. In the fastest shift log, boost crosses the target in 1.3 seconds, and in this case, boost had only dropped to 5.8 psi; a much higher starting point but basically the same duration for boost to build!
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      03-29-2020, 04:46 AM   #48
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Nezil, I've dug a bit more and my theory is this:

During shifts, if anything, the ECU is trying to SLOW DOWN the turbine when you think you need it more. Because:

1) Although DV dumps boost, the turbo shaft speed is still high. It's already high enough to support top end charge air (check MAF) which is too much for next gear.

2) The dumped (via DV) charge air goes into turbine housing, adding more pressure.

I'm not sure if BMW uses turbo shaft speed sensor though I know for sure Nissan does with the great VQ30.

ECU simply decides 80+% is the maximum WG duty to give when you need to SLOW DOWN the turbine, or there'd too much overshoot to deal with after boost target is met.

As RPM rises and turbine slows down, it gets to a point where turbine is not overloaded (for the RPM). Then 100% WG duty is allowed.

I do not think 80% makes a much slower spool up unlike what you see from your log. It could be the DV working in conjunction on 100% duty when allowed.

I've been logging boost behavior on DCT shift for a long time, because it plays a key role in acceleration and safety. My finding is that overshoot is a much more serious issue and takes 500-1000 RPM normally to settle. More boost headroom you leave, more poised the engine will be taking it up, hence the less power loss or you even make more power (by properly eating more boost!). Halim has a "boost guideline" tuning strategy (I made up that name and won't go deeper on it), with that there are even more uncertainties.

In any cases, the priority on shift is always boost dumping and turbine adjusting/decreasing. There is no way for 100% WG duty instantly on tap, unless you're already significantly under-boost before shift, which would be a much more horrible scenario.

In this sense, to "fix the lag" will be on less pedal down time. DCT fixes it by shifting impossibly fast, not by forcing 100% WG duty.
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      03-29-2020, 09:09 PM   #49
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Quote:
Originally Posted by SeanWRT View Post
Nezil, I've dug a bit more and my theory is this:

During shifts, if anything, the ECU is trying to SLOW DOWN the turbine when you think you need it more. Because:

1) Although DV dumps boost, the turbo shaft speed is still high. It's already high enough to support top end charge air (check MAF) which is too much for next gear.

2) The dumped (via DV) charge air goes into turbine housing, adding more pressure.

I'm not sure if BMW uses turbo shaft speed sensor though I know for sure Nissan does with the great VQ30.

ECU simply decides 80+% is the maximum WG duty to give when you need to SLOW DOWN the turbine, or there'd too much overshoot to deal with after boost target is met.

As RPM rises and turbine slows down, it gets to a point where turbine is not overloaded (for the RPM). Then 100% WG duty is allowed.

I do not think 80% makes a much slower spool up unlike what you see from your log. It could be the DV working in conjunction on 100% duty when allowed.

I've been logging boost behavior on DCT shift for a long time, because it plays a key role in acceleration and safety. My finding is that overshoot is a much more serious issue and takes 500-1000 RPM normally to settle. More boost headroom you leave, more poised the engine will be taking it up, hence the less power loss or you even make more power (by properly eating more boost!). Halim has a "boost guideline" tuning strategy (I made up that name and won't go deeper on it), with that there are even more uncertainties.

In any cases, the priority on shift is always boost dumping and turbine adjusting/decreasing. There is no way for 100% WG duty instantly on tap, unless you're already significantly under-boost before shift, which would be a much more horrible scenario.

In this sense, to "fix the lag" will be on less pedal down time. DCT fixes it by shifting impossibly fast, not by forcing 100% WG duty.
Forgive me if I get this wrong because I'm just a layperson here.

So, if I understand you correctly, there is no fix for a 6MT car if this is designed in to prevent boost overshoot?

Could you lower the boost or torque target so the overshoot is safe? I know you might then be leaving power on the table, but at least you wouldn't "feel" the lag?
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      03-29-2020, 09:41 PM   #50
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First off SeanWRT, thank you so much for giving your opinion. I know you've said previously that you don't have much experience with 6MT, but you do have a lot of experience reading logs and understanding how our DME works - and that is super valuable!

The other thing I want to thank you for is having a second opinion. I've been looking at logs since going with BM3 (as you know), and I've got my own opinions about what's going on, but without anyone to bounce these ideas and opinions off, it's very difficult to make any progress.
Quote:
Originally Posted by SeanWRT View Post
Nezil, I've dug a bit more and my theory is this:

During shifts, if anything, the ECU is trying to SLOW DOWN the turbine when you think you need it more. Because:

1) Although DV dumps boost, the turbo shaft speed is still high. It's already high enough to support top end charge air (check MAF) which is too much for next gear.
I've checked the logs as you suggested, but MAF doesn't seem too high to me. After the shift, MAF stays at the same point until WGDC hits 100%, then rises as boost rises. MAF seems quite aligned with boost, and consequently low after the shift.

Assuming the shaft speed is too fast, are you suggesting that the waste gate is effectively letting the turbine free-wheel a bit to avoid a shock which would slow it down if the waste-gate were to close?
Quote:
2) The dumped (via DV) charge air goes into turbine housing, adding more pressure.
It sounds to me like you're saying we've lost boost but the turbine is still spinning too fast. Would a DV which vents to atmosphere help slow the turbine down so that the DME doesn't prevent boost from building?
Quote:
I'm not sure if BMW uses turbo shaft speed sensor though I know for sure Nissan does with the great VQ30.
I don't think BMW has that. There are certainly no additional connectors on the turbo housing.
Quote:
ECU simply decides 80+% is the maximum WG duty to give when you need to SLOW DOWN the turbine, or there'd too much overshoot to deal with after boost target is met.

As RPM rises and turbine slows down, it gets to a point where turbine is not overloaded (for the RPM). Then 100% WG duty is allowed.
How could the DME know this if it weren't for a shaft speed sensor? You've suggested that MAF is too high, but it doesn't look like it in the logs... unless I'm missing something.
Quote:
I do not think 80% makes a much slower spool up unlike what you see from your log. It could be the DV working in conjunction on 100% duty when allowed.
But you do agree that boost is building slower with a quicker shift than a slower one, based on my logs. I realise that boost gets to target quicker when the shift is quicker, but the rate boost builds is actually slower if the shift is faster.
Quote:
I've been logging boost behavior on DCT shift for a long time, because it plays a key role in acceleration and safety. My finding is that overshoot is a much more serious issue and takes 500-1000 RPM normally to settle. More boost headroom you leave, more poised the engine will be taking it up, hence the less power loss or you even make more power (by properly eating more boost!). Halim has a "boost guideline" tuning strategy (I made up that name and won't go deeper on it), with that there are even more uncertainties.

In any cases, the priority on shift is always boost dumping and turbine adjusting/decreasing. There is no way for 100% WG duty instantly on tap, unless you're already significantly under-boost before shift, which would be a much more horrible scenario.
This isn't what the logs show... the log for the slower > 2.0s shifts show WG duty instantly going to 100%. Boost was above target before both shifts 2nd to 3rd & 3rd to 4th.
Quote:
In this sense, to "fix the lag" will be on less pedal down time. DCT fixes it by shifting impossibly fast, not by forcing 100% WG duty.
Isn't DCT fixing the lag because there is no period out of WOT, not because of the speed of the shift. Obviously the shift speed is what allows this, but it's not the shift speed that's significant, it's the constant WOT that is.
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      03-29-2020, 10:45 PM   #51
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I went back and looked at logs again re. boost build speed. Here are the results:


Some caveats though... Boost building isn't a linear effect. The gradient (psi of boost built / second) isn't an exact representation of the speed boost builds in each case, but it is an indication.

As you can see, the absolute duration that boost builds for before crossing boost target is longer if you shift slower, but the rate at which boost builds is faster.

A faster shift is undoubtably quicker overall, but it could be quicker still if there is some way of speeding up the boost build rate by closing the waste gate.

If there is some way of building boost quicker, the biggest effect will be found with reasonably fast shifts ~1.4 seconds.

I firmly believe that shifting at 1.4 seconds should be considered a 'fast' shift. It's not super aggressive, but it's also not slow. A 0.7s shift, while possible, is not comfortable for passengers or for the drivetrain. Those of you with 6MT that can capture logs, take a look at your shift times. I'd be surprised if anyone can make shifts quicker than 1.0s on the street day to day.
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      03-30-2020, 06:02 AM   #52
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Nezil, thanks for taking time on my reply.

By referring to MAF, I was not saying it's high during shifts (because of DV and throttle intervention). Instead I wanted to tell the flow difference at top end and middle range. And how critical it is for DME to dump flow and adjust turbine on shift where rpm goes down.

Flow is turbine speed.
Boost is Flow divided by RPM.
WG%+RPM = pressure on turbine = the change rate of turbine speed, not turbine speed.

DME is backing off WG duty. And not seeing a maxed out WG duty seems to be your frustration. But WG duty doesn't make instant impact. And in this case, with other elements in play, 80% makes minimal difference from 100%, and is not why it's laggy.

Either this build-in feature can be defeated or not, you may really want to take a second thought about it...
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      04-05-2020, 11:31 AM   #53
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On my focus RS, I disconnected the recirc valve controller and ran it straight from manifold pressure. Don’t know if this is possible or would help in this situation but this is just a thought..
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      04-05-2020, 04:43 PM   #54
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Quote:
Originally Posted by Nezil View Post
Quote:
Originally Posted by SeanWRT View Post
Hi Nezil, noticed you updated days ago, but didn't have time for a second look at log until now.

The WG behavior does seem abnormal. As when pedal fully back on, the boost delta is big enough to warrant a 100% WG duty but it held back a little to 80%.

Has it been consistently that way?

I suspect the safety action was still being taken at that moment, if the unsettling RPM is any indication. It could be the clutch not being fully engaged or the uneven road surface (less likely as I know what log would've been like).

WG is 100% for a short time (when RPM settles) before it goes down to 80% again which is normal - when boost is close enough to target, WG% goes down to prevent from overshoot, something you can find out for yourself if you floor it off boost and from low rpm.

Please take a look from other logs, specifically at WG behavior after 100% pedal.
Always thanks to you SeanWRT, for taking the time to respond. I've been busy myself and now only find the time to respond.

First off, I'm really glad and encouraged that you can see the WG behaviour seeming to be abnormal. To answer your question... Yes, it has always been that way, every single time I shift. Stock and tuned, with and without FBO parts.

The unsettling RPM is probably clutch shudder as it re-engages, particularly 1st to 2nd or 2nd to 3rd shifts, I can do logs of 3rd to 4th pretty easily and you'll see less of it there, but the same WG behaviour; I don't think they're related. The WG delay is always and consistently exactly 1 second; it really does look suspiciously like a software thing.

I'll try to gather some more logs, but this WG behaviour is consistent for my car. One thing I'd like to try is letting of the gas, and dipping the clutch but not shifting. This should indicate if the WG behaviour is linked to the clutch signal, as I suspect.

widetyres suggests that Porsches had a similar behaviour in the past?
Quote:
In the end, I'm positive 100% WG won't solve the problem with 1.4s shift...Key is still off pedal time. As you see from DCT log, the system is able to hold boost during shift and for most of the time is dealing with overboost.
Of course. I can capture a log with a quicker shift, but I am certain it won't be different. I'm not expecting DCT performance at all, and I totally expect 6MT to be compromised in performance for that reason.

The WG closing properly should reduce the total lag down to true turbo lag, which is fine, and only what I'm trying to achieve.
Yeah my passengers have even mentioned it.

The lag feels like some safety precaution especially coupled with the rev hang from 1-2, it becomes truly frustrating.

I can't even hardly get the car to chirp the rear end into second most of the time as it's so far off power.

I have noticed it's not nearly as bad in efficient+mdm, if you drive that setting hard it adapts to feel like a big power N/A engine with a huge spool at the bottom of the pedal. It is truly the most satisfying experience for me.

Sport plus just makes me mad because of that lag. Makes the car feel jerky and unsmooth.

Except for some shifts! Sometimes it's pure bliss and behaves exactly how I know it should and could in s+... but that's rare.

It just feels wrong and artificially held back most of the time.
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      04-05-2020, 05:31 PM   #55
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There's probably a legitimate reason they tuned the 6spd manual version this way. Maybe to compensate for the variability of different drivers shifting and avoiding an overboost situation. Much easier with the DCT since they know exactly how that will shift.

I'd rather just deal with it by shifting faster/higher revs vs messing around with the wg response. But i'll be happy to watch as others beta test any tuning attempts to fix.
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      04-10-2020, 06:35 AM   #56
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Nezil, any update from PTF?
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      04-10-2020, 07:52 AM   #57
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Quote:
Originally Posted by PackPride85 View Post
There's probably a legitimate reason they tuned the 6spd manual version this way. Maybe to compensate for the variability of different drivers shifting and avoiding an overboost situation. Much easier with the DCT since they know exactly how that will shift.

I'd rather just deal with it by shifting faster/higher revs vs messing around with the wg response. But i'll be happy to watch as others beta test any tuning attempts to fix.
Could be. The lag doesn't exist on the 1M as far as I know, and while N54 is older, it's at least one turbo car that doesn't have it. Both the N55 and S55 M cars have this issue and they have different turbo setups. I wonder if it's present on N55 135i? If not, I lean towards this being some kind of traction or safety oriented "feature".
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      04-10-2020, 10:32 AM   #58
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Quote:
Originally Posted by SeanWRT View Post
Nezil, any update from PTF?
Sorry for the delay everyone... I've found that this whole 'working from home' thing has been far more stressful and far less time for looking in to issues like this.

Actually I'm a bit disappointed with where we got to with PTF. Initial tests showed promise, but didn't really improve much in any significant way.

I feel like I've provided quite a lot of data, and a lot of data analysis, and though I was getting new maps initially that must have had some changes, I never found out exactly what these changes were, and it honestly feels like some confusion about what I'm trying to address.

I keep hearing the consistent responses of:
  • Shift faster
  • 6MT isn't as fast as DCT
The first of which I've tried, and this makes the situation worse, not better (unless the revs are high enough for boost not to drop as much), and the second isn't really that helpful; it's obvious.

What makes this all the more frustrating is that NVM in the UK claim that they have a fix for this, but aren't prepared to do remote tuning. Either they're making a false claim, or they're one of the only tuners that knows what's needed to tune out this waste-gate closing delay.

So far, SeanWRT's suggestion that it could be related to turbo shaft speed is the best I've heard, but this isn't what's being suggested by PTF.

I really do want to work more on this, and I'll reach out to PTF one more time and see if they're interested, but if not, it might be time to ask some other tuners familiar with this platform and see if they have any insight.

SeanWRT, I've heard you say in the past that the throttle response of the N55 is good. Ordinarily I'd agree with you, but between shifts in 6MT is pretty awful. A fast shift can cause nearly an entire second before boost really starts to build again. Technically the throttle is fully open, but the feeling of throttle response is very delayed.
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Last edited by Nezil; 04-10-2020 at 11:54 AM..
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      04-11-2020, 10:22 AM   #59
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Quote:
Originally Posted by Nezil View Post
Sorry for the delay everyone... I've found that this whole 'working from home' thing has been far more stressful and far less time for looking in to issues like this.

Actually I'm a bit disappointed with where we got to with PTF. Initial tests showed promise, but didn't really improve much in any significant way.

I feel like I've provided quite a lot of data, and a lot of data analysis, and though I was getting new maps initially that must have had some changes, I never found out exactly what these changes were, and it honestly feels like some confusion about what I'm trying to address.

I keep hearing the consistent responses of:
  • Shift faster
  • 6MT isn't as fast as DCT
The first of which I've tried, and this makes the situation worse, not better (unless the revs are high enough for boost not to drop as much), and the second isn't really that helpful; it's obvious.

What makes this all the more frustrating is that NVM in the UK claim that they have a fix for this, but aren't prepared to do remote tuning. Either they're making a false claim, or they're one of the only tuners that knows what's needed to tune out this waste-gate closing delay.

So far, SeanWRT's suggestion that it could be related to turbo shaft speed is the best I've heard, but this isn't what's being suggested by PTF.

I really do want to work more on this, and I'll reach out to PTF one more time and see if they're interested, but if not, it might be time to ask some other tuners familiar with this platform and see if they have any insight.

SeanWRT, I've heard you say in the past that the throttle response of the N55 is good. Ordinarily I'd agree with you, but between shifts in 6MT is pretty awful. A fast shift can cause nearly an entire second before boost really starts to build again. Technically the throttle is fully open, but the feeling of throttle response is very delayed.
I’ll ask my tuner if he knows about it or has a fix
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      04-15-2020, 12:33 AM   #60
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So the latest is that PTF has closed my support ticket as resolved, which is disappointing.

I sent some emails and had a phone call this morning to see if I could find any more evidence for this being a known issue and more importantly, if there has ever been evidence of a fix.

My phone call was to Pure Turbos, mostly because I have considered upgrading the turbo on my car, but if this waste gate issue cannot be improved, I don't think I'll be bothering. To my surprise, the guy I talked with there said that this has been a known issue since the N54, and present with the N55 and S55 motors. He had a 600whp 6MT N54 based car and couldn't stand the excessive lag between shifts. Since then he's been auto or DCT precisely because of this. He did think that times had changed since his experience however, and felt that there were initially fixes such as the WOT Box, which is an aftermarket No Lift Shift / Two Step piggyback box for 6MT cars, JB4 has a relay based solution, and more recently flash tunes to address the issue.

I've now also sent emails to several tuners in the US, basically asking them if they're interested in working on a solution to this problem together. I'm prepared to pay for a custom tune with them, but only if they're able to address this behaviour.

As of now, I'm still waiting to hear back from the tuners I've contacted, but will keep this thread updated if I hear anything.
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      04-16-2020, 08:43 AM   #61
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I don't have graphs or science to provide you guys but I can say that on my car if I hold the tcs button and turn everything off the car doesn't appear to cut off throttle or power between shifts.
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      04-16-2020, 10:43 AM   #62
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Quote:
Originally Posted by Nezil View Post
So the latest is that PTF has closed my support ticket as resolved, which is disappointing.

I sent some emails and had a phone call this morning to see if I could find any more evidence for this being a known issue and more importantly, if there has ever been evidence of a fix.

My phone call was to Pure Turbos, mostly because I have considered upgrading the turbo on my car, but if this waste gate issue cannot be improved, I don't think I'll be bothering. To my surprise, the guy I talked with there said that this has been a known issue since the N54, and present with the N55 and S55 motors. He had a 600whp 6MT N54 based car and couldn't stand the excessive lag between shifts. Since then he's been auto or DCT precisely because of this. He did think that times had changed since his experience however, and felt that there were initially fixes such as the WOT Box, which is an aftermarket No Lift Shift / Two Step piggyback box for 6MT cars, JB4 has a relay based solution, and more recently flash tunes to address the issue.

I've now also sent emails to several tuners in the US, basically asking them if they're interested in working on a solution to this problem together. I'm prepared to pay for a custom tune with them, but only if they're able to address this behaviour.

As of now, I'm still waiting to hear back from the tuners I've contacted, but will keep this thread updated if I hear anything.
Pay only when they show you example it works. Should be easy if they actually did it.

I don't think any tuner ever fixed it by now.

IMO, there may be some way to force WG close 100% but it wouldn't fix lag.
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      04-16-2020, 11:14 AM   #63
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Originally Posted by SeanWRT View Post
Pay only when they show you example it works. Should be easy if they actually did it.

I don't think any tuner ever fixed it by now.
Thanks SeanWRT, I'll try to keep the thread updated with what I hear. I'm hopeful that I can find a tuner who is interested in working on this with me. I'm happy to pay if they can, but really feel that this is something that will give them a unique sales proposition to 6MT owners if they manage it.

Quote:
IMO, there may be some way to force WG close 100% but it wouldn't fix lag.
I've been doing some thinking about exactly what I'm hoping for, and you're absolutely right, there is no way to eliminate lag, and I'm not expecting or even hoping for that.

What I'm talking about is actually a daily drive-ability feature, for when you're driving at 7/10s or 8/10s. Most tuners focus only on 10/10s behaviour, and maybe that is what 90% of their customers care about; it's certainly important. If you're driving at 10/10s, you can shift in 0.7s at redline, and the behaviour I'd like investigated is masked to the point of being not important. It's when you drive at anything less than 10/10s you feel it, and you feel it bad.

The reason it's so objectionable isn't because there is lag, it's because of the way the lag feels. If you look at the screen shots I posted, when shifting from 2nd to 3rd, boost does build even with the WG at 80%, but as soon as it shuts, boost builds far more rapidly, and you feel this as a driver and passenger. Since the rate of change is greater on a 2nd to 3rd shift, you feel it far more there than in other gears.

If the WG closes 100%, as it does if you slow shifts down to 2 seconds, boosts builds much more progressively and you don't get this sudden surge. It makes the car uncomfortable for passengers and slower than it needs to be. Does that make more sense?
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      04-22-2020, 01:30 AM   #64
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Waiting to talk to you for a week, registering for this forum is a nightmare.

Here M2 is a $100K car, $50K used for a first generation M2. You're about to drop your 15 years of savings on this car then luckily you learn of all this BS (and the crank hub, got to love that "superior" german engineering). Which no paid shill "journalist" has ever mentioned even though it's present since N54 cars, and nobody on youtube is ever talking about so they don't look stupid with their compromised manual clout mobile in front of the people they are "influencing".

If I had the car here are the people that I would talk to in my part of the globe, they have a reputation for being some of the best BMW tuners:

Gelashvili Performance (Mr. George Gelashvili)
- https://www.geptuned.com
- based in Georgia, they do remote tuning when not touring USA

THP Solutions (Mr. Zic)
- http://thp.solutions/
- based in Croatia, I don't think they remote tune, but worth inquiring about the issue in general
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      04-22-2020, 04:46 AM   #65
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Originally Posted by C0YS View Post
I don't have graphs or science to provide you guys but I can say that on my car if I hold the tcs button and turn everything off the car doesn't appear to cut off throttle or power between shifts.
[UPDATE: Srub this post! I did some more testing and the delay is still very noticeable even with DSC off - the log didn't save for some reason though so don't have that to share]

I agree with this. I don't have a log for it, but I switched DSC off the other night and the under 5K gear changes felt like they had ~50-60% less lag (compared to sport+).

Nezil This could suggest that the lag is a DSC imposed issue, rather than an DME mapping issue. Perhaps this is a DSC "feature" (e.g. to reduce transmission shock or wheelspin).

I will do a log when I can to compare.

Last edited by widetyres; 05-02-2020 at 01:49 AM..
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      04-22-2020, 01:02 PM   #66
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Hi all... I haven't been doing nothing on this, but wanted to wait until I had anything meaningful to report before posting.

I've started working with a tuner who has been good enough to look at addressing this behaviour first, before working on a full custom tune for my car.

If we're successful, I'll let everyone know, and provide evidence that it's improved or eliminated.

If we're not successful, I won't be posting about who I worked with out of respect to them; they will have tried, but I wouldn't want that to be looked at as a reflection of how good they are at tuning for what 90% of customers want.

This seems to be a complex issue that PTF were either unwilling to spend time on (and to be fair, I wasn't paying for their time) or unable to fix. I'm still hopeful and optimistic, but conscious that this might take a while.
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