[eluzbet]

Not sure if you read the first post, but I've flashed back to the factory tune at 8psi of boost and still getting the same corrections. I've had the corrections for about a year now, I've tried probably over 20 different gas stations during different seasons. Its also winter so Iat's are around 60-80 degrees right now and I see no improvement in corrections from them I'll try adding a total of 4 gallons but unfortunately I'm doubtful it will help.

Originally Posted by Gizm0

You're targetting 18.6psi with stock turbos, they will produce a lot of heat. Doesn't help that you are in FL. Even if you have an upgraded FMIC, it will knock and pull timing unless you either reduce the boost target, or get higher octane fuel.

2.5 gallons of E85 in a 16 gallons tank will get you an octane rating of 95. That's assuming the ethanol is actually E85, and assuming good quality 93 octane gas, but as mentioned above, during winter, the ethanol content is most likely lower. If the ethanol is only E70, and you get gas from a shitty gas station, I wouldn't be surprised if you end up with even lower octane than 93, even with 2.5 gallons of E70. Up your ethanol content a little, I usually put about 4 gallons in mine during the winter to end up with E30 mix, and it pulls hard with no timing corrections, boost target is 19psi.

Also if you always get gas from the same gas station, try switching up. Where I live for example, I found out that Shell was causing timing pulls like yours, but gas from Sams Club out of all places worked much better with minimal timing corrections.

[Gizm0]

Originally Posted by eluzbet

Not sure if you read the first post, but I've flashed back to the factory tune at 8psi of boost and still getting the same corrections. I've had the corrections for about a year now, I've tried probably over 20 different gas stations during different seasons. Its also winter so Iat's are around 60-80 degrees right now and I see no improvement in corrections from them I'll try adding a total of 4 gallons but unfortunately I'm doubtful it will help.

I did not see a datalog for stock map, so can't tell for sure, but even bone stock N54s will see timing corrections from time to time, the knock sensors are just really sensitive on these cars. Check this page, about half way down, do some reading about N54 timing. Pretty good stuff.

https://bmwtuning.co/bmw-n54-data-lo...1rZPt5DYz4wTPV

[eluzbet]

I'll take a look at it, I'll also try to get a log for the stock map whenever I can. I appreciate it thank you

Originally Posted by Gizm0

I did not see a datalog for stock map, so can't tell for sure, but even bone stock N54s will see timing corrections from time to time, the knock sensors are just really sensitive on these cars. Check this page, about half way down, do some reading about N54 timing. Pretty good stuff.

https://bmwtuning.co/bmw-n54-data-lo...1rZPt5DYz4wTPV

[zxing]

I've been trying to figure out the exact same issue on my car. I'm running a similar setup as you (7.5" stepped intercooler, downpipes, Delphi coils, OEM Bosch spark plugs, index 12 injectors, 93 octane, walnut blasted). I also get 2-6 degree timing corrections constantly across most or all cylinders, even on a stage 0 tune, no fault codes. I have gone through basically the same process of eliminating the likely suspects - coils, plugs, injectors, bad gas. I didn't try ethanol, but did try running 93 octane on a 91 tune with no improvement.

The only thing I can add is that with low IAT's (like 28 degrees) the corrections aren't as bad, but still there during every pull.

Have you borescoped your cylinders? I have a very high mileage motor and I have a lot of carbon buildup on my pistons. At this point I can't really thinking of anything else other than the carbon deposits hotspotting and causing preignition.

Stage 0 log: https://datazap.me/u/zxing/logs/rmhy...7zepmd75tokiqr
Stage 1, 91 tune: https://datazap.me/u/zxing/logs/ackz...m4tzp0b2rp3n6t
Stage 1+, 28 degree IAT: https://datazap.me/u/zxing/logs/wgmc...o35o405feg74zc