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      05-09-2013, 09:29 AM   #7624
marv85
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Drives: '07 E92 335i MT
Join Date: Jun 2010
Location: Bay Area

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Quote:
Originally Posted by JHR View Post
Here's the situation:
I have Cobb and PTF protune running 20% ethanol/93 octane (3 gallons E85 in a tank with balance 93 Shell). BMS DCI and Helix FMIC. No DPs.
35,000 miles on original coils.
Changed plugs 4000 miles ago.

All of my cylinders are quiet with essentailly no timing corrections. But once the oil temps reach about 230F, cylinder 1 timing shows corrections up to -9 degrees in stop and go, daily driving. Air temp 68F. All the other cylinders are quiet, perhaps only -3 deg timing corrections here and there in DD (AFR about 14 or 15).
Note: I don't see any timing drops in any cylinders during WOT pulls (AFR -> 12).

Question: why is only cylinder 1 showing the -9 degree timing corrections in DD driving, but not WOT?

I'm thinking that as the plugs are pretty new, but the coils are original, it may be coil #1.

Your thoughts?
as enrita said it's totally normal, to further alleviate your fears, your tune has stock timing targets at those low loads. So these timing drops were always there, you just weren't looking for them.

if you want to do the experiment yourself load the OTS race map in ATR, copy the timing table ans paste it on the stage 0 map. compare where the changes were done and you'll see what I'm saying
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'07 E92 335i 6MT- HP650, inlets/outlets, ER FMIC, VRSF CP, LPFP stg2, CSF rad, 'is Aux rad, ER OC, Ohlins, M control arms, eibach front sway bar.
'05 C55 AMG
SOLD - '22 Tesla M3P | '10 E92 335i M, 6MT COBB, FBO, st2 LPFP, Mfactory LSD | '07 E90 335i, PTF COBB E50, FBO, HFS4
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