[designatedposter]

Originally Posted by cookiesowns

Turbos help with timing due to better flow and lower IAT. If tuned properly it will definitely knock less.

Those timing pulls don't seem too bad.

For comparison here's a log that targets 91 octane levels of boost, with 91-93 levels of timing.

This is just my 2nd revision on the M2 after I finally had time to dial it in..

http://www.bootmod3.net/log?id=5b268b6ad10b4304d3cee4ca

http://www.bootmod3.net/log?id=5b268dd6d10b4304d3cee4ce


Timing correction on 3rd gear because I shifted hard and aggressive from 2nd chirping the tires and causing traction control to kick in

http://www.bootmod3.net/log?id=5b268c71d10b4304d3cee4cd



Sorry man, been too busy.. barely had time to drive the M2 recently.

i want to stress that i'm using 93 octane fuel with e85 added to e20 level to try to boost octane. all this on a 91 octane tune. i am still getting timing issues. after looking at your first log, your timing is impeccable, no drops and all cylinders in sync.

with that said, you think my timing drops is acceptable?

[cookiesowns]

Originally Posted by designatedposter

i want to stress that i'm using 93 octane fuel with e85 added to e20 level to try to boost octane. all this on a 91 octane tune. i am still getting timing issues. after looking at your first log, your timing is impeccable, no drops and all cylinders in sync.

with that said, you think my timing drops is acceptable?

I need to see more logs to be certain. But based on what I see, and remember about the OTS maps.. yeah they don't seem terrible..


But the fact that you need to add 10% ethanol on top of E10 93 octane on a 91 map... it seems... not the best IMO.

Do you have some logs on regular pump 91 on the 91 map?

[horsepower_and_hounds]

http://www.bootmod3.net/log?id=5b238975d10b4304d3cede55

http://www.bootmod3.net/log?id=5b238990d10b4304d3cede5c

http://www.bootmod3.net/log?id=5b2389bed10b4304d3cede5d

Here are couple on straight 93 and stg 2 93 map v5.3. Ambient was 74deg. Did a 3rd, 4th, 5th got screwed up so deleted and a 3/4/5 shift. My IAT's are still high but I didn't find any major issues. These are back to back pulls. I have been running without booster for about 7 tanks now

[SeanWRT]

@designatedposter cookiesowns
As for why bigger turbo ignites better, IAT and flow capacity don't really matter.

It's the significant lower back pressures that makes a difference. This is how:
1) Freer flow turbine restricts less at any given shaft rpm.
2) Bigger turbo needs less shaft rpm to make any given boost/flow.

Some may ask will down pipe help in the same way? Yes it will, just to a way less extent as a component downstream of turbo. Hot half of turbo (turbine + manifold in one piece) play the dominant role dictating back pressure among all that is "engine back". It's easily understood when you imagine exhaust gas flow gets out of cylinders, enters turbine housing and 'hits' turbine directly to drive it.

Anything else, including downpipe, is downstream and only gets what turbine filters.

Generally, anything lowering turbo shaft speed reduce back pressure, and thus helps ignition. For example - turbo inlet pipe, downpipe & catback exhaust. But they're just too insignificant compared to turbo. No one really gets meaningfully better timing, just because of installing any or all of them. Most guys gets perfect timing on OTS STG2 with bigger intercooler only.

[cookiesowns]

Originally Posted by SeanWRT

@designatedposter cookiesowns
As for why bigger turbo ignites better, IAT and flow capacity don't really matter.

It's the significant lower back pressures that makes a difference. This is how:
1) Freer flow turbine restricts less at any given shaft rpm.
2) Bigger turbo needs less shaft rpm to make any given boost/flow.

Some may ask will down pipe help in the same way? Yes it will, just to a way less extent as a component downstream of turbo. Hot half of turbo (turbine + manifold in one piece) play the dominant role dictating back pressure among all that is "engine back". It's easily understood when you imagine exhaust gas flow gets out of cylinders, enters turbine housing and 'hits' turbine directly to drive it.

Anything else, including downpipe, is downstream and only gets what turbine filters.

Generally, anything lowering turbo shaft speed reduce back pressure, and thus helps ignition. For example - turbo inlet pipe, downpipe & catback exhaust. But they're just too insignificant compared to turbo. No one really gets meaningfully better timing, just because of installing any or all of them. Most guys gets perfect timing on OTS STG2 with bigger intercooler only.

Thanks for the detailed explanation, you always go above and beyond when answering questions from forum members!

Yes, better IAT & flow capacity are a by product of a less restrictive turbo design ( compressor/turbine )

Well if you stick within the efficiency range of the turbo and tune for your particular car, mod, and fuel, you can definitely get better timing and "smoother" overall power delivery as I've shown with my new logs on an early revision of my map.

14psi stock turbo stock downpipe is plenty for me. This is the safe spot for lap after lap track days for me.

[SeanWRT]

@cookiesowns thank you for the kind words. To me, sharing is a big part of tuning fun.

[designatedposter]

Originally Posted by cookiesowns

I need to see more logs to be certain. But based on what I see, and remember about the OTS maps.. yeah they don't seem terrible..


But the fact that you need to add 10% ethanol on top of E10 93 octane on a 91 map... it seems... not the best IMO.

Do you have some logs on regular pump 91 on the 91 map?

appreciate the feed back, here is a log with regular old e10 93 octane, using the same 91 oct tune.
http://www.bootmod3.net/log?id=5b1dc12ad10b437faba93f6e

for reference, here is the e20 log once again. same ots tune as above.
http://www.bootmod3.net/log?id=5b25db99d10b4304d3cee419

i've a general question, does sport mode change the spool behavior? i notice that sport mode has much less turbo lag as compared to comfort, DTC, or DSC off mode. i've even tried to stomp on the pedal in comfort mode to try to simulate the sport mode throttle mapping, but it still seems that sport mode is much less lag. i recall there were tables for spool parameters..

[cookiesowns]

Originally Posted by designatedposter

appreciate the feed back, here is a log with regular old e10 93 octane, using the same 91 oct tune.
http://www.bootmod3.net/log?id=5b1dc12ad10b437faba93f6e

for reference, here is the e20 log once again. same ots tune as above.
http://www.bootmod3.net/log?id=5b25db99d10b4304d3cee419

i've a general question, does sport mode change the spool behavior? i notice that sport mode has much less turbo lag as compared to comfort, DTC, or DSC off mode. i've even tried to stomp on the pedal in comfort mode to try to simulate the sport mode throttle mapping, but it still seems that sport mode is much less lag. i recall there were tables for spool parameters..

Ouch.. that's knock heavy without ethanol. I still see some minor corrections on the E20 91 log but it's not bad at all. I'd be content running that E20 log day to day.

Correct in sport mode the WGDC bias is a little bit different. DME will keep WGDC closed at 100% until it needs to bleed off boost. Same goes for sport_. DSC Off should have the same throttle mapping.

[designatedposter]

i've got fresh logs of a different local shell gas station! it's about 30 cents more expensive per gallon, but seems worth it, take a look.

m235i n55 ewg
stage 2 91 octane tune
shell 93 octane fuel
3rd gear pulls (6mt)

log 1: CLEANEST log i have ever had, textbook. this gas station looks really promising
http://www.bootmod3.net/log?id=5b2c2bc5d10b430873d738df

log 2: taken shortly after log 1, but shows timing drops reminiscent of my typical logs.. knock at 4700 rpm..what's your take on it? insignificant increase in IAT.
http://www.bootmod3.net/log?id=5b2c2d8cd10b430873d738e1

i'm going to flash the stage 2 93 tune and test later tonight.

[Nezil]

I might be wrong, but I think you need to get more logs. I've seen some people get logs for 3rd, 4th and 5th gear pulls, which is great for a long hard pull, but it's difficult to repeat because it's so fast.

In the past, I've seen logs from SeanWRT that were multiple third gear pulls back to back.

I find it difficult to do straight back to back pulls, but I can get 6 or 7 third gear pulls in about 10 minutes.

With that many pulls you can get an idea of consistency. If you look at some of my bad logs earlier in the thread, you'll see that sometimes one of my 6 pulls is perfect, even though later or earlier pulls are a mess.

Consistency is important, and you cannot tell that from only two pulls in a session.

[horsepower_and_hounds]

Originally Posted by Nezil

I might be wrong, but I think you need to get more logs. I've seen some people get logs for 3rd, 4th and 5th gear pulls, which is great for a long hard pull, but it's difficult to repeat because it's so fast.

In the past, I've seen logs from SeanWRT that were multiple third gear pulls back to back.

I find it difficult to do straight back to back pulls, but I can get 6 or 7 third gear pulls in about 10 minutes.

With that many pulls you can get an idea of consistency. If you look at some of my bad logs earlier in the thread, you'll see that sometimes one of my 6 pulls is perfect, even though later or earlier pulls are a mess.

Consistency is important, and you cannot tell that from only two pulls in a session.

Well now that is a lot of third gears. Good point but my issue with 3rd gear is I feel it is not long enough or enough load to really tax the HPFP, FMIC, etc. That is what I always pay more attention the 4th & 5th. On the old M4 and my M2 if they're was any failures under stress it was in 5th. M4 would trim out in 5th when mixing & boost would always peak in 5th. The M2 HPFP failed at 5.2k in 5th when mixing for me and went limp. Also when testing the FMIC 4th and 5th are what really heats it up. I mean your not going to do street racing pulls in 3rd, you maybe might start there or 1/4 mile......most of the time for me running the back roads I am between winding out 3rd & solid in 4th.

Example when I dyno'd my car suffered low power due to heating up. So when doing 3rd gear pulls the temp would actually drop then barely return to where it started by the time the run was over and that is great for vendors to advertise this but in the real world you really don't use that. when you get deep in a 4th run is when the load is long enough to test damage control of the support parts FMIC/HPFP and by the time your in 5th this is where most failures are in my opinion. That is why I always post 3/4/5 independent runs then a 3/4/5 shift to see component recovery.

That is just my experience from the past 3 cars, not to argue any other opinions. The last 3 BMW's I have had that were piggybacked or tuned always had issues in 5th.

mainly do thirds to get the component heating process going to really see what is going to happen on the 4th 7 5ths

[SeanWRT]

IAT and ignition would suffer more as gear goes up. Boost curve would be a little different too.

Though HPFP stress would be the same if not lower due to thinner air out of higher IAT.

Originally Posted by m2ruder

Well now that is a lot of third gears. Good point but my issue with 3rd gear is I feel it is not long enough or enough load to really tax the HPFP, FMIC, etc. That is what I always pay more attention the 4th & 5th. On the old M4 and my M2 if they're was any failures under stress it was in 5th. M4 would trim out in 5th when mixing & boost would always peak in 5th. The M2 HPFP failed at 5.2k in 5th when mixing for me and went limp. Also when testing the FMIC 4th and 5th are what really heats it up. I mean your not going to do street racing pulls in 3rd, you maybe might start there or 1/4 mile......most of the time for me running the back roads I am between winding out 3rd & solid in 4th.

Example when I dyno'd my car suffered low power due to heating up. So when doing 3rd gear pulls the temp would actually drop then barely return to where it started by the time the run was over and that is great for vendors to advertise this but in the real world you really don't use that. when you get deep in a 4th run is when the load is long enough to test damage control of the support parts FMIC/HPFP and by the time your in 5th this is where most failures are in my opinion. That is why I always post 3/4/5 independent runs then a 3/4/5 shift to see component recovery.

That is just my experience from the past 3 cars, not to argue any other opinions. The last 3 BMW's I have had that were piggybacked or tuned always had issues in 5th.

mainly do thirds to get the component heating process going to really see what is going to happen on the 4th 7 5ths

[Nezil]

I think you both (SeanWRT & m2ruder) missed my point. I wasn't being critical of 3rd, 4th and 5th gear pulls, on the contrary, I think they provide additional information that 3rd gear only pulls may not provide. I'm therefore basically in agreement with you both.

My point was simply that one or two logs only may be missing something, particularly if your two logs aren't identical. If you get one good and one bad, how do you know what's going on? You need to get several logs in similar conditions to get a sense of what's 'normal' behaviour for your engine in those same conditions (ambient temp, map, fuel etc.), and two logs may not be enough to do that.

[horsepower_and_hounds]

Originally Posted by Nezil

I think you both (SeanWRT & m2ruder) missed my point. I wasn't being critical of 3rd, 4th and 5th gear pulls, on the contrary, I think they provide additional information that 3rd gear only pulls may not provide. I'm therefore basically in agreement with you both.

My point was simply that one or two logs only may be missing something, particularly if your two logs aren't identical. If you get one good and one bad, how do you know what's going on? You need to get several logs in similar conditions to get a sense of what's 'normal' behaviour for your engine in those same conditions (ambient temp, map, fuel etc.), and two logs may not be enough to do that.

Opps my bad Nezil. Now I get it

[designatedposter]

I finally confirmed that i have an octane issue, and not a hardware issue.

Whilst investigating this octane issue with local fuel in central Connecticut, i still had some concern that it could also be hardware issue since i exhibited similar timing pull with new jersey fuel.

I had the chance to fill up with Mobil 93 in northeast Pennsylvania and the logs show it all. Perfect timing. This confirms that my local fuel is not up to snuff and even the so called 93 octane does not exceed 91..

logs of stage 2 91 octane tune
n55 ewg m235i
93 octane Mobil fuel from northeast PA
http://www.bootmod3.net/log?id=5b38d5ced10b437334792d1e
http://www.bootmod3.net/log?id=5b38f27ed10b437334792d38
http://www.bootmod3.net/log?id=5b38f3aed10b437334792d3c
http://www.bootmod3.net/log?id=5b396bd9d10b437334792dc5

so... who has heard any updates on the ACN 91 tune from PTF? This is a tune specific to the low quality fuel such as california

[designatedposter]

Looking for feedback on this HPFP crash at 4800 rpm. I just switched to the M2 stage 0+ map and have been liking is so far, but on a 3rd gear pull I felt like I hit a wall and car was burble’ing whilst WOT. The log shows HPFP issue at 4800rpm. What do you guys think? is this a fluke or do i have a hpfp issue? running shell 93 octane, no additional ethanol.

also, stage 2 91 octane maxed at 14.7 psi, this m2 map is quite a bit higher at 17.. is this normal?

http://www.bootmod3.net/log?id=5b670cccd10b431620dbbe6c

m235i
catless DP
FMIC
HPFP: crashing at 4800rpm
Timing: terrible
Boost: 17 psi max

[ICantDrive4Sht]

Here is a 3-5 gear log on Bm3 stg2 ots tune. Timing seems to be all over the place.

http://www.bootmod3.net/log?id=5b33c40dd10b4310d12e1420

Here is similiar log with Enzo tune

http://www.bootmod3.net/log?id=5b4460bad10b437911b1c9e6

If anyone here is interested to look at these, what do you think? With Enzo timing atleast seems to be much cleaner.

[MTWO]

Your BM3 log looks good to me but Enzo one seems pretty bad. You have boost overshooting target and your throttle closing quite a bit in the Enzo one. You don’t have these happen in the BM3 log. Maybe try a different gas station next time but to be honest from all I’ve seen its just inevitable on just pump gas to have timing move like that here and there.

[cookiesowns]

Originally Posted by designatedposter

Looking for feedback on this HPFP crash at 4800 rpm. I just switched to the M2 stage 0+ map and have been liking is so far, but on a 3rd gear pull I felt like I hit a wall and car was burble’ing whilst WOT. The log shows HPFP issue at 4800rpm. What do you guys think? is this a fluke or do i have a hpfp issue? running shell 93 octane, no additional ethanol.

also, stage 2 91 octane maxed at 14.7 psi, this m2 map is quite a bit higher at 17.. is this normal?

http://www.bootmod3.net/log?id=5b670cccd10b431620dbbe6c

m235i
catless DP
FMIC
HPFP: crashing at 4800rpm
Timing: terrible
Boost: 17 psi max

I really don't recommend running the M2 0+ map on a EWG car... it's not made to work well on the regular N55 ROMs. It's good to use as a baseline to learn how to self tune, but not at all for a "map" on a EWG car.

Run the 91 stage 2 OTS.

[cookiesowns]

Originally Posted by MTWO

Your BM3 log looks good to me but Enzo one seems pretty bad. You have boost overshooting target and your throttle closing quite a bit in the Enzo one. You don’t have these happen in the BM3 log. Maybe try a different gas station next time but to be honest from all I’ve seen its just inevitable on just pump gas to have timing move like that here and there.

Throttle closures aren't a horrible thing as long as it's not inducing timing corrections which it wasn't here.. But I suspect the enzo tune has modified knock thresholds.

However the ENZO tune is simply too aggressive for the guys car in that climate.

[designatedposter]

Originally Posted by cookiesowns

I really don't recommend running the M2 0+ map on a EWG car... it's not made to work well on the regular N55 ROMs. It's good to use as a baseline to learn how to self tune, but not at all for a "map" on a EWG car.

Run the 91 stage 2 OTS.

Care to elaborate? Does it have to do with the extra tables of the M2 tune over the stock m235i tune?

[ICantDrive4Sht]

Originally Posted by cookiesowns

Throttle closures aren't a horrible thing as long as it's not inducing timing corrections which it wasn't here.. But I suspect the enzo tune has modified knock thresholds.

However the ENZO tune is simply too aggressive for the guys car in that climate.

Thx for feedback.
By "that climate" you mean it *could be better if it was colder? Those temps are very rare here where i live.