Knock

gdub · 10-11-2011, 04:45 PM

Hey do any of you all get knock when running the aggressive 301 map logging from your accessport?

I'm getting some timing corrected on all cylinders when boost hits 15.8 (from what the accessport log says). I'm using Shell 93 gas. This is happening in 3rd gear (I can't really get a full pull in fourth, there are no air strips around here). Basically at 5k (right after the shift) all cylinders correct 3 degrees of timing and taper off until 6200 but then Cylinder 5 corrects 3 degrees again at 6300 rpm until shift.

Is this happening to anyone else? Or is my car about to blow up?

Regardless I'm going to take the aggressive map off and put on the sport map and try it again to see results.

ErvGotti · 10-11-2011, 07:00 PM

Send the logs to Cobb to see what they say. It could be a number of factors from bad gas to carbon build up. Also post some logs over on E90 post that is usually where most of the N54 hobbiest that know how to read logs are.

Fundahl · 10-11-2011, 07:52 PM

On my 135i, if I went over 13psi on pump 93 for long pulls I would get timing pulled (90F weather). I think it could just be an over aggressive boost target. The DME does a very good job at keeping things safe, but I would definitely run a map that doesn't cause ignition timing to be retarded.

gdub · 10-12-2011, 09:44 AM

thanks guys.

rader1 · 10-12-2011, 10:32 AM

The DME pulls timing when IATs go above a fixed point(a little over 100F IIRC) so that could well be the problem. Log some pulls showing timing correction, IATs and boost and then post up the actual logs will help to figure out whats going on. If you do post this on e90post id do it in the official cobb thread, there is a huge tuner war going on right now and your question will likely turn into a flaming match and not get answered

JBurer · 10-12-2011, 11:24 AM

gdub - Cobb is reasonably responsive if you email using the website contact.
Will you please post your findings here, when you have an answer?

COBB Tuning · 10-12-2011, 11:25 AM

Send me a copy of your log and I'll be more than happy to take a look at it for you!

Ian
ian@cobbtuning.com

10-11-2011, 04:45 PM	#1
gdub Private First Class 18 Rep 144 Posts Drives: none Join Date: Apr 2011 Location: dfw iTrader: (0)	Knock - Cobb Hey do any of you all get knock when running the aggressive 301 map logging from your accessport? I'm getting some timing corrected on all cylinders when boost hits 15.8 (from what the accessport log says). I'm using Shell 93 gas. This is happening in 3rd gear (I can't really get a full pull in fourth, there are no air strips around here). Basically at 5k (right after the shift) all cylinders correct 3 degrees of timing and taper off until 6200 but then Cylinder 5 corrects 3 degrees again at 6300 rpm until shift. Is this happening to anyone else? Or is my car about to blow up? Regardless I'm going to take the aggressive map off and put on the sport map and try it again to see results.
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10-11-2011, 07:00 PM	#2
ErvGotti Major 124 Rep 1,362 Posts Drives: 2008 135i 6MT Join Date: Jul 2010 Location: Aviano iTrader: (5) Garage List 2008 135i [6.00]	Send the logs to Cobb to see what they say. It could be a number of factors from bad gas to carbon build up. Also post some logs over on E90 post that is usually where most of the N54 hobbiest that know how to read logs are.
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10-11-2011, 07:52 PM	#3
Fundahl Captain 8 Rep 704 Posts Drives: VO 1M, 300zx TT Join Date: Mar 2011 Location: Corpus Christi, Texas iTrader: (0)	On my 135i, if I went over 13psi on pump 93 for long pulls I would get timing pulled (90F weather). I think it could just be an over aggressive boost target. The DME does a very good job at keeping things safe, but I would definitely run a map that doesn't cause ignition timing to be retarded.
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10-12-2011, 09:44 AM	#4
gdub Private First Class 18 Rep 144 Posts Drives: none Join Date: Apr 2011 Location: dfw iTrader: (0)	thanks guys.
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10-12-2011, 10:32 AM	#5
rader1 Banned 70 Rep 2,197 Posts Drives: Cobb Stage 2+ 135i Join Date: Apr 2011 Location: Roanoke, VA iTrader: (0)	The DME pulls timing when IATs go above a fixed point(a little over 100F IIRC) so that could well be the problem. Log some pulls showing timing correction, IATs and boost and then post up the actual logs will help to figure out whats going on. If you do post this on e90post id do it in the official cobb thread, there is a huge tuner war going on right now and your question will likely turn into a flaming match and not get answered
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10-12-2011, 11:24 AM	#6
JBurer Private First Class 16 Rep 144 Posts Drives: 2008 135i, 1991 911 Turbo Join Date: Apr 2008 Location: Dallas, TX iTrader: (0)	gdub - Cobb is reasonably responsive if you email using the website contact. Will you please post your findings here, when you have an answer?
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10-12-2011, 11:25 AM	#7
COBB Tuning Major 233 Rep 1,051 Posts Drives: 335i Join Date: Dec 2010 Location: Austin, TX iTrader: (0)	Send me a copy of your log and I'll be more than happy to take a look at it for you! Ian ian@cobbtuning.com
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