2.0L LNF Performance Tech 260hp and 260 lb-ft of torque Turbocharged tuner version.

Knock

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Old Jul 30, 2013 | 04:34 PM
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Knock

So ever since i got torque ive been watching sensors and notice that my KR generally stays at zero however when i get on it a little ive seen around -3 ish. Is that bad? Trying to learn more about what is normal for all these sensors.
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Old Jul 30, 2013 | 04:38 PM
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I have 0-3 degrees of knock randomly driving too. its normal on an LNF. High load high RPM knock is the bad kind, but even then sometimes its false knock.
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Old Jul 30, 2013 | 05:19 PM
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From: Arizona
Originally Posted by leemanfor
I have 0-3 degrees of knock randomly driving too. its normal on an LNF. High load high RPM knock is the bad kind, but even then sometimes its false knock.
Elaborate
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Old Jul 30, 2013 | 06:11 PM
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Originally Posted by 10CSSTC
Elaborate
Well, false knock is knock that jumps to a high number immediatly. ZZP explains it best.

Real KR is KR that grows with engine RPM and engine load. It depends entirely on detonation, which is dependent upon throttle position, MAF, MAP, engine load, engine temperature, and RPM. As RPM and engine load increase, the chance for KR (or higher KR) increases. As the vehicle shifts to the next gear, KR will usually make a small jump up as well due to the higher engine load.

False knock is characterized by a sharp spike to an immediately high value of KR followed instantly by the KR Recovery Rate. It doesn’t grow with engine RPM or load, it jumps to a high value on throttle input and then recovers to a low value, or zero perhaps, as engine RPM continues to increase. Note that this is exactly opposite to the characterization of REAL KR. Remember, knock is simply specific noise detected by engine microphones. Because it happens to fall with in the frequency of real KR does not necessarily mean that it IS real KR.
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Old Jul 30, 2013 | 07:16 PM
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From: Arizona
Originally Posted by leemanfor

Well, false knock is knock that jumps to a high number immediatly. ZZP explains it best.

Real KR is KR that grows with engine RPM and engine load. It depends entirely on detonation, which is dependent upon throttle position, MAF, MAP, engine load, engine temperature, and RPM. As RPM and engine load increase, the chance for KR (or higher KR) increases. As the vehicle shifts to the next gear, KR will usually make a small jump up as well due to the higher engine load.

False knock is characterized by a sharp spike to an immediately high value of KR followed instantly by the KR Recovery Rate. It doesn’t grow with engine RPM or load, it jumps to a high value on throttle input and then recovers to a low value, or zero perhaps, as engine RPM continues to increase. Note that this is exactly opposite to the characterization of REAL KR. Remember, knock is simply specific noise detected by engine microphones. Because it happens to fall with in the frequency of real KR does not necessarily mean that it IS real KR.
So basically this is normal? I was running 89 octane when i saw this. Will my usual 91 octane resolve this?
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Old Jul 30, 2013 | 09:16 PM
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Higher octane will always have a better chance of solving knock. The higher the octane number the more resistance to knock it has. So yes you should always run 91+ in my opinion.
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Old Jul 30, 2013 | 11:08 PM
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From: canada
Originally Posted by 10CSSTC
So ever since i got torque ive been watching sensors and notice that my KR generally stays at zero however when i get on it a little ive seen around -3 ish. Is that bad? Trying to learn more about what is normal for all these sensors.
don't worry about it, these cars do that even on stock tune.
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Old Jul 30, 2013 | 11:09 PM
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Originally Posted by 10CSSTC
So basically this is normal? I was running 89 octane when i saw this. Will my usual 91 octane resolve this?
iv run 91 and 94 and I still see it, don't worry, its normal
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Old Jul 30, 2013 | 11:11 PM
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From: CA
Originally Posted by tomj77
don't worry about it, these cars do that even on stock tune.
Do they? I am Trifecta tuned at 23 PSI and when I turn my tune on I heard weird noises coming from the car. It sounds like some clicking noises and something weird like computer noises or something(idk how to explain the noise). Then when I turn the tune off, it goes away. So I'm pretty sure when I turn the tune on it's making that noise. Is this normal? J/w. Thanks.
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Old Jul 30, 2013 | 11:31 PM
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the clicking is probably your injectors and hpfp

knock is no bueno. you want as little as possible. get the highest pump gas octane you can at all times
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Old Jul 31, 2013 | 08:39 AM
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yes run 91+. Higher octane has better chance to resist knock.
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Old Jul 31, 2013 | 08:55 AM
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Originally Posted by ae_xiong
Do they? I am Trifecta tuned at 23 PSI and when I turn my tune on I heard weird noises coming from the car. It sounds like some clicking noises and something weird like computer noises or something(idk how to explain the noise). Then when I turn the tune off, it goes away. So I'm pretty sure when I turn the tune on it's making that noise. Is this normal? J/w. Thanks.
Need a lot more info, and a video with good sound quality of the sound (start a new thread)
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Old Aug 1, 2013 | 05:02 AM
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From: CA
Originally Posted by ECaulk
Need a lot more info, and a video with good sound quality of the sound (start a new thread)
IDk how to describe it and it's not bothering me enough to make a video. LOL I only hear it when I turn on the tune. But maybe it is just my injectors. LOL I can also hear my CAI a lot more now too after the tune. But it does make some weird computer noises and stuff. Also, I am running on 91 octane. Sadly, there's nothing higher than that from where I live (Fresno, CA) Oh well, as long as it still runs fast and don't start breaking down on me then it should be ok. I'm actually debating on upgrading to a 2012 Camaro ss too. Nice interior plus bone stock 1/4 mile is 13 flat= Winner. Throw on some basic bolt ons and tune then it will = rape. LOL
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