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      05-18-2018, 11:49 PM   #1
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A tale of two datalogs, and a question about timing... [New logs from BM3 91 Stage 2]

I've been looking into the datalogs I've been capturing, and I'm seeing some very inconsistent timing numbers that I think show a problem. I'm just not sure what the problem is...

I'm currently running the BM3 93 AKI OTS Stage 2 map, with ~93.25 AKI fuel made up of 91 AKI Chevron gas mixed with 100 AKI Sunoco Race gas mixed just over 3:1

Luckily, m2ruder was kind enough to post some logs of his car running the exact same map, and his timing results look much better. In his post, he does say that he's running approximate octane of 94 ~ 95 AKI, so slightly higher than me, but he doesn't give details on what this fuel is, if it contains ethanol, or if it was achieved with an octane booster etc.

The other differences between my car and m2ruder's are I have a FabSpeed sport Cat installed, FTP Charge Pipe and the stock FMIC; CSF in on the way, and I made sure that my IATs are below 100 F. m2ruder had at the time of his logs, a VSRF Stepped Street FMIC; no DP.

For reference, m2ruder's logs are here:
http://www.bootmod3.net/log?id=5ac1fc1cd10b4305f5db48e7
http://www.bootmod3.net/log?id=5ac1fc3bd10b4305f5db48e8
http://www.bootmod3.net/log?id=5ac1fc60d10b4305f5db48e9

My log that I'm using to compare is here:
http://www.bootmod3.net/log?id=5afefe5fd10b4377e10a83e8

I've summarised the data in two ways - extracts of the important data at 3,000, 4,000, 5,000 and 6,000rpm, and screen captures of the relevant sections of the graphs. I realise that cherry picking the data may not give a clear indication of the issues, which is why I've linked the full data log set. The summaries do definitely show the issue I'm seeing though - m2ruder's logs are so clean!



m2ruder's graph:


My graph:
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Last edited by Nezil; 05-20-2018 at 01:33 AM..
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      05-19-2018, 12:26 AM   #2
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Obviously, octane is a possibility, but there are of course other things that it could be. I have considered IAT, but my timing issues start when the IAT is only 90 F.

I have also considered HPFP, but the lowest pressure throughout my pull is 2,465psi. It does dip a little, but not massively. Could this be enough to cause issues?

There are no knock detected points during my pull, which I was seeing even with the stock tune on straight 91 AKI pump gas. That's a good thing, but could my issues still be related to California gas? Even with race fuel mixed in?

Is there anything else I should be considering? I'd really rather not change spark plugs or run octane booster, but I could perhaps increase the ratio of race gas or try adding some E85?

I imagine this timing behaviour isn't going to damage my engine, I'm just loosing out on a fair amount of power and torque, is that a fair statement?
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      05-19-2018, 06:20 AM   #3
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Nezil,
Sorry it was missed...I think if you go looks over my posts I noted the octane booster and content but here you go.

I was using the MMT based Lucas booster due to confirmed consistent tested results by many and not snake oil. I was running consistently aprox 7.5 oz per tank (1/2 but) and based on their formula should give a 1.5 oct bump. Now it might be slightly more since the mixing is not perfect science. Might have over 1/2 tank and put 1/2 btl in so concentration will be higher. Then also you always have the residual factor.

Anyway it never pulled timing when using it. Now I stopped using it and did some pulls and had timing pull and a couple of "knock" notations non some logs and then it got hot and the car pulls timing all over the place. Am working on upgrading to a HD intercooler to fight the IAT's. My dyno runs would start at 85 deg and top out at 150. On the road it will be at 95 on cruz then under wot it will drop a couple of deg then climb up to 130 this clean air flow.

So I have proved the booster works to control the timing pull and knock but it can't help the high IAT's. Oh and it turns your shit orange/brown, plugs, exhaust tips, 02 sensors, etc

Now i am trying the E30 map. Boost was a little low on the first pulls but I only started with 2 gal (E21). I am going up to 3 gal next. Keeping an eye on the HPFP

What gears you doing your logs in? I try to always do independent 3/4/5 then a multi shift 3-4-5 and if I don't post them all I try to reference 5th gear if I can since it puts a 1-1 load on the car and that is usually when my HPFP was crashing

Let me know if you have any other questions
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      05-19-2018, 08:33 AM   #4
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Nezil ...you're starting to worry me given we loaded this tune around the same time. How do I record these logs and graphs? I will do it today and post up my results for some comparison and analysis. Also...do you notice anything physically wrong with the car (I.e. sputtering, etc.) while doing these pulls? I ask so I know what to look for as my car "feels" fine. Lastly, what is the best way to do the pull? I assume open highway as I'll get to speed pretty quickly.
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      05-19-2018, 09:34 AM   #5
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Open hwy
TC off, switch to manual shift if DCT
2k to redline but at least past 6k

FYI 5th gear will be pretty fast at redline... knocking on 150 fyi

If your using the app just hit log button (blue the turns red) then WOT when done hit log again (red button then turns to blue)

They will be uploaded to the BM3 cloud where you can go into the log in the app and copy the link like below.

http://www.bootmod3.net/log?id=5afaab94d10b435e87b2d6f1


Then anybody can access it for review
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      05-19-2018, 12:13 PM   #6
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Quote:
Originally Posted by m2ruder View Post
Nezil,
Sorry it was missed...I think if you go looks over my posts I noted the octane booster and content but here you go.

I was using the MMT based Lucas booster due to confirmed consistent tested results by many and not snake oil. I was running consistently aprox 7.5 oz per tank (1/2 but) and based on their formula should give a 1.5 oct bump. Now it might be slightly more since the mixing is not perfect science. Might have over 1/2 tank and put 1/2 btl in so concentration will be higher. Then also you always have the residual factor.
This is great information, but what was/is your base fuel. Are you saying that on straight 93 AKI pure gas (not E10) pump gas you were getting timing pull when your IATs were still low? If that's the case, shouldn't the BM3 OTS 93 AKI tune be more accurately called 94+ AKI?

The Stage 2 OTS tune looks really great... 17.2 psi boost target with good timing and no HPFP crashing up to redline!... but it doesn't seem to work out on 93 AKI pump gas?

Quote:
Anyway it never pulled timing when using it. Now I stopped using it and did some pulls and had timing pull and a couple of "knock" notations non some logs and then it got hot and the car pulls timing all over the place. Am working on upgrading to a HD intercooler to fight the IAT's. My dyno runs would start at 85 deg and top out at 150. On the road it will be at 95 on cruz then under wot it will drop a couple of deg then climb up to 130 this clean air flow.

So I have proved the booster works to control the timing pull and knock but it can't help the high IAT's. Oh and it turns your shit orange/brown, plugs, exhaust tips, 02 sensors, etc.
Yeah, I'm sure it does work, but I really don't like the thought of the orange / brown deposits! If I can achieve the same thing with Race Gas or E85, that is certainly preferable. Looks like you're in the process of doing the same thing!
Quote:
Now i am trying the E30 map. Boost was a little low on the first pulls but I only started with 2 gal (E21). I am going up to 3 gal next. Keeping an eye on the HPFP
The biggest issue with mixing E85, is that it's inconsistent. E85 should be E85 in the summer, but in the winter is more likely E70. You get your blend nailed at one point of the year, and it's way off the next! At least Race Gas should be more consistent... albeit more expensive.
Quote:
What gears you doing your logs in? I try to always do independent 3/4/5 then a multi shift 3-4-5 and if I don't post them all I try to reference 5th gear if I can since it puts a 1-1 load on the car and that is usually when my HPFP was crashing
It's tough to find a stretch of road with enough length, no traffic and no cops to achieve a pull to redline in any gear, let alone 4th or 5th. I also have an issue with IAT because I have the stock FMIC currently; I'm still waiting for my CSF FMIC to arrive. So, to answer your question directly... I'm doing pulls in 3rd usually, sometimes 4th. 5th is pretty much out of the question I'm afraid.
Quote:
Let me know if you have any other questions
Thanks.
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      05-19-2018, 12:19 PM   #7
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Quote:
Originally Posted by m2ruder View Post
Open hwy
TC off, switch to manual shift if DCT
2k to redline but at least past 6k

FYI 5th gear will be pretty fast at redline... knocking on 150 fyi

If your using the app just hit log button (blue the turns red) then WOT when done hit log again (red button then turns to blue)

They will be uploaded to the BM3 cloud where you can go into the log in the app and copy the link like below.

http://www.bootmod3.net/log?id=5afaab94d10b435e87b2d6f1


Then anybody can access it for review
I don't have the app. Do I need any additional hardware for the app? How does it connect to the car? I loaded the map with my pc. I assume I can use that to log if need be?
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      05-19-2018, 12:45 PM   #8
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Quote:
Originally Posted by F87_LCI View Post
I don't have the app. Do I need any additional hardware for the app? How does it connect to the car? I loaded the map with my pc. I assume I can use that to log if need be?
See below
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      05-19-2018, 12:47 PM   #9
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Quote:
Originally Posted by F87_LCI View Post
I don't have the app. Do I need any additional hardware for the app? How does it connect to the car? I loaded the map with my pc. I assume I can use that to log if need be?
You can use the the program on the PC just plug in the e-net cable like you did to flash and just go to dashboard and in top right corner is the log button and put laptop on front seat or floor. To use the phone there is a agent device you can buy and set up but the laptop will do for now.
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      05-19-2018, 12:52 PM   #10
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The agent device is just a Raspberry Pi 3B (not 3B+). You can assemble one for less than $50, and I think it's worth it at that price.
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      05-19-2018, 04:01 PM   #11
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I have a rasp pi (made a retro gaming console out of it, but I never use it). Can you point me in the right direction on how to set it up for this purpose?
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      05-19-2018, 05:20 PM   #12
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Quote:
Originally Posted by F87_LCI View Post
I have a rasp pi (made a retro gaming console out of it, but I never use it). Can you point me in the right direction on how to set it up for this purpose?
Funny... I repurposed an RPi I wasn't using either!

The instructions you need are here: https://bootmod3.atlassian.net/wiki/...irmware+Update

Extract the firmware to a micro SD card, plug it in, and you're good to go. I reconfigured the WiFi settings on mine to work with my phone Hotspot and my home WiFi, but you don't need to do that either of you don't want. Instructions for that are also on the bootmod3 wiki.

The hardware agent device is just an RPi in a $7.00 enclosure. I actually bought the same enclosure because the one I had was a bit open for my liking, but there is no need to do that.
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      05-19-2018, 05:59 PM   #13
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It's way off topic, but if it helps you to gather datalogs for your car so that we can compare... I'm all for it!

I mounted my RPi under the drivers seat with velcro on to the top of the rear passenger vents there.

I ran an E-Net cable from there around the front of the subwoofer enclosure, through a gap in the carpet the other side, and under the door trim round to the OBD location. At the OBD location I installed a slim OBD extension I got from Amazon, and put the connectors up under the dash. If you remove the panel above the pedals (2 10mm nuts and a few clips), there is plenty of space to tuck the plug and socket.

For power, I decided that I probably didn't need to hard wire it permanently, so I just ran a fairly long USB cable down the side of the seat. If I want to plug it in, I do so in either the under arm-rest socket, or the one in front of the gear stick. I considered a more permanent power setup, but once I'm happy with a tune, I probably wouldn't need it plugged in all the time.

This keeps the wires and RPi out of the way of my feet, arms etc. while I'm driving. Phone in the cup holder to start and stop logging, and it's all pretty clean.
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      05-19-2018, 10:47 PM   #14
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OK, it's evening, and my kids are in bed, so it's time for some log capturing...

Based on the assumption that the issue is related to octane, I've flashed the 91 AKI Stage 2 map to my car. Keeping in mind that I should have a ~93.25 AKI blend in my tank currently, I expect to see no timing pull with this map.

I do have about 2 gallons of 100 octane race fuel left in a gas can in the garage, and I might try adding that to the tank once the level is down a little more. I calculate that if I get to 5.5 gallons of my 93.25 blend left in the tank, and add 2 gallons of 100, I'll get 95.05 AKI. I'll probably wait until the BMW connected app says I have 5 gallons left, and then add my 2 gallons though, which in theory would give me a 95.2 AKI. Once I've done that, I'll switch back to the 93 AKI tune and try logging again.

If I'm not too tired, I'll report back on this later tonight with my logs!
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      05-20-2018, 01:32 AM   #15
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OK, here we go... 8 datalogs of BM3 Stage 2 91 Octane OTS map v5.3. Adaptations were reset about 10 minutes before these runs, so the first few runs will be during adaptation taking place. I expect the adaptation to be complete by the later runs though.

All of these are third gear pulls from under 3,000rpm up to redline. DSC was off for all runs except the 5th one, which is obvious because the throttle angle keeps reducing as traction was lost.

Outside temperature was ~60F / 15C. Fuel was a 3:1 mix of Chevron 91 pump gas, and Sunoco SS100 Race Gas, giving a combined octane of 93.25.Hopefully I can get some help interpreting this data. I'm concerned that I'm still getting timing pull after adaptation on the 91 Octane OTS map with 93.25 octane fuel.

I had hoped to switch back to the 93 Octane OTS map and get some more pulls logged, but for some reason wasn't able to change maps, and the car got into an odd state where I also couldn't datalog. Disconnecting the battery for 3 minutes fixed this, and the car still ran fine, but it meant that I couldn't do any more runs this evening.

In all honesty, these 91 Octane Stage 2 map logs don't really look any better than the ones I'd taken previously with the 93 Octane Stage 2 map. I had thought initially that things were getting better and better with each run, and put this down to DME adaptation. Run 4 though, was the best of the bunch, and Run 8 even has 0.2 degrees of retarded timing at one point, just as I saw in the 93 Octane Stage 2 map logs.

Could this really be octane related? I'm also wondering if it could be AFR related because the ratio is pretty rich under hard load at high revs with this map, but I'm clutching at straws...

Any help or suggestions would be most welcome!

Charts:












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Last edited by Nezil; 05-25-2018 at 06:36 PM..
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      05-23-2018, 11:35 AM   #16
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I'm down to ~5 gallons of my 93.25 Octane blend, and it's been 5 days since I took the logs above. I'm going to capture a few more logs today with the same blend and see if DME adaptation has improved anything, and then add the remaining 2 gallons of 100 octane race fuel that I have and capture some more.

The theory is that if the timing events improve with a higher octane blend, my issues are octane related, and unfortunately that means that the BM3 91 Octane Stage 2 OTS tune really isn't a 91 Octane tune, but a tune requiring greater than 93 octane fuel.

If the logs look good with the higher octane blend, I'll step things up to the 93 Octane Stage 2 OTS tune and see if I can get consistently good timing with my new higher octane blend there as well.

... Watch this space!
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      05-23-2018, 12:36 PM   #17
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OK, I got the first two parts of my plan done... 4 datalogs with the current 93.25 octane blend, and then the last 2 gallons of my 100 octane race gas added to the remaining 4 gallons of 93.25, giving me an effective octane of 95.5 AKI.

Here are the logs:And here are the charts to go with those logs:






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      05-23-2018, 12:41 PM   #18
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Run 1 above looks REALLY good. This is what I want all, or at least most of my logs to look like.

Runs 2, 3, and 4 are more typical though, and I just can't see what's causing the timing pull.

I will say that cylinder 3 seems to consistently have more timing pull than other cylinders, but it's certainly not alone in having timing pull. I'm not sure if this is relevant or not.

There are no recorded knock events, but I guess it's possible that there are some detected and not logged.

Since the first log is the best, another possibility that might come to mind is that the IATs might be lower and gradually increasing. This is true, IAT at the start of run 1 is 83.3, and at the start of the other runs, it's a few degrees higher, but it is only a few. IAT at the end of run 1 is 108.95, and at the end of run 2, which is arguably the worst run for timing pull, it's 114.35. Having said that, the timing pull on run 2 starts when the IAT is still below 100!

proTUNING Freaks, do you have any suggestions?
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      05-23-2018, 01:43 PM   #19
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OK, more data. Just to recap, this is the BM3 91 Octane Stage 2 OTS map, running with a 95.5 AKI mix of regular CA 91 pump gas and 100 octane Race Gas.
And the charts:




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      05-23-2018, 01:46 PM   #20
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Run 2 is great, Run 3 isn't bad, and Run 1 is maybe slightly better than the 93.25 AKI mix.

proTUNING Freaks / SeanWRT / FSociety / cookiesowns, I really need some insight on this... Should I really be expecting to see timing pull with 95.5 AKI fuel on the 91 Octane Stage 2 OTS map?
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      05-23-2018, 10:29 PM   #21
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Nezil, you looked a little too nervous and obsessed with your recent posts, which I refrained from commenting on. I wanted to see what you find out yourself and who else would stand out to explain things for you.

To me, simply the gas you have does not perform to the claimed octane rating. And mixing different gas or adding additive are known to be inconsistent in many cases. My suggestions for you are:
1) Log stock map on 100% 91OCT and compare for yourself. See how good a job BMW is doing in your case.
2) Request a map update (to lower timing advance) thru BM3 APP if you don't have better gas to have consistent access to.

A little knowledge sharing:

Timing correction is the nature of DME (N54/N55/S55) timing control. DME works at edge of knock threshold for maximum efficiency out of each combustion stroke. You ever do, or see someone else do a dyno tuning of our car, you will know super clean timing curve don't make highest power, instead you're leaving a lot of reliable and consistent power on the table. You better either raise the boost or advance timing or both, so DME find knock threshold again to work at. A good tune is not to over/under-advance the ignition timing for a given octane at the given boost level and AFR. Pursuing zero timing corrections at all times is not possible, nor is it necessary, whatever octane/boost/timing/afr you run.

BTW, where I'm at with my custom map, I have just as many if not a little more timing correction than the 3 logs you posted above. I can trade a little boost or rail pressure for cleaner timing, but in my opinion it's not worth it.
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      05-24-2018, 03:59 PM   #22
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Drives: LCI '18 6MT M2
Join Date: Jul 2017
Location: San Francisco Bay Area

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Quote:
Originally Posted by SeanWRT View Post
Nezil, you looked a little too nervous and obsessed with your recent posts, which I refrained from commenting on. I wanted to see what you find out yourself and who else would stand out to explain things for you.
Well I appreciate you responding in the end... I realise that I'm not a 'normal' M2 owner, in that I like to do everything myself, or at least understand the things that I am not doing myself. I'm also a perfectionist, which can be tiring for everyone, including me!

When it comes to mechanical work, this is easy; I can install all my own bolt ons, do my own window tinting, PPF, Paint Correction and Ceramic Coating install etc.

When it comes to performance modifications, the M2 is my first forced induction car, and my first BMW, so I obviously have a fair amount to learn. I don't expect to become an expert so that I can do my own tuning (though that might be fun way down the road), but I hope to understand the changes that a tuner makes to optimise a map for a car, its mods, location and fuel type, and also understand logs, because they're the most valuable data we get about how the engine is running in our cars.

The problem with this desire, is that there isn't much information out there on tuning turbocharged BMWs. Most owners are happy just to pay a tuner, and not be bothered with the 'how' of what was done, just enjoy the results. To me, learning about the how is just as much fun as the end result!

You, cookiesowns, and FSociety all seem to have gained knowledge over time, and I hoped there would be a way for me to do the same. In the interests of sharing with the community, I made a thread on understanding data logs. This was of course for my benefit, but I hoped that forum members with more knowledge than me would help to flesh this out for the benefit of everyone.

Quote:
To me, simply the gas you have does not perform to the claimed octane rating. And mixing different gas or adding additive are known to be inconsistent in many cases. My suggestions for you are:
1) Log stock map on 100% 91OCT and compare for yourself. See how good a job BMW is doing in your case.
That's a great idea, thank you. I have captured some rough logs in the past on the stock tune, and do know that the stock map results in quite a lot of timing pull and is also littered with 'knock detected' points in normal use.

As you know, this scared me in the past, and adding in 100 Octane Race Gas got rid of the 'knock detected' points entirely. It didn't get rid of the timing pull though.

I guess the main thing I was wanting to know, is if my car has anything fundamentally wrong with it. If the stock map results in data logs that are full of knock events and timing pull, is that because my engine has a problem, or is that just normal for California gas?
Quote:
2) Request a map update (to lower timing advance) thru BM3 APP if you don't have better gas to have consistent access to.
I actually did this already, though not in as direct a way as you've said. I made a map update request in BM3 about a week ago, but got no response.

proTUNING Freaks did say that they were thinking of making some OTS maps for ACN 91 Octane fuel. I'd be happy to help test that, and even do some dyno runs if that's needed, but they've not responded at this point.

Quote:
A little knowledge sharing:

Timing correction is the nature of DME (N54/N55/S55) timing control. DME works at edge of knock threshold for maximum efficiency out of each combustion stroke. You ever do, or see someone else do a dyno tuning of our car, you will know super clean timing curve don't make highest power, instead you're leaving a lot of reliable and consistent power on the table. You better either raise the boost or advance timing or both, so DME find knock threshold again to work at. A good tune is not to over/under-advance the ignition timing for a given octane at the given boost level and AFR. Pursuing zero timing corrections at all times is not possible, nor is it necessary, whatever octane/boost/timing/afr you run.
Thanks very much for this description, but it does raise another question:

If the DME is capable of doing all of these corrections to prevent knock, why doesn't a map simply target the highest timing & boost, and just have the DME perform the corrections. Would I be correct in understanding it like this:
The DME is capable of limiting boost and timing to protect the engine from knock, but relying solely on the DME to do this is not going to be optimal, and doesn't give you much of a fail safe.

The most optimal situation, would be to target boost and timing to just over the point where timing will be pulled by the DME. The DME is then only correctly slightly, rather than a lot.

As you've said, it would be possible to target boost and timing to the point where timing never gets pulled, but this would be a conservative map that doesn't make optimal power.
Quote:
BTW, where I'm at with my custom map, I have just as many if not a little more timing correction than the 3 logs you posted above. I can trade a little boost or rail pressure for cleaner timing, but in my opinion it's not worth it.
That's helpful to know, I appreciate that.
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2018 ///M2 LCI, LBB, 6MT...

Current Performance Mods:
CSF FMIC, ER CP, Fabspeed Cat, Aquamist WMI, GFB DV+, NGK 97506, BM3 (Stage 2 93 OTS), CDV delete, UCP, M2C/M3/M4 Strut Brace, M3/M4 Reinforcement Rings
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