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Captain Thread Killer returns
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5point7 said:
Is a little knock retard okay? At about 30% throttle, I'm getting 0.53 Knock retard.

ONCE in a while it will get past 1.0
From what I have heard some knock is ok, supposedly if your getting knock at WOT its bad.......the gear heads will be along to give you more informative info though
 

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Captain Thread Killer returns
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Blitzu said:
Knock retard is not bad for the motor, knock reatrd is the preventative measures taken by the PCM to control engine knock.

.53 degrees of knock is nothing at all... it is most likely false knock. False knock could be created from a gear shift... or some suspension bumping against the trans or motor. Just some examples. Low octane could produce knock, bad gas could produce knock. So seeing .53 degrees is not going to do anything. The point where you would want to start really paying attention is when you start to see 5 degrees or more. It is important to also see where the knock degree is occuring.

Is it right at launch and then goes to 0 quickly? Does it show the knock when you let off the gas after a WOT run? Or does it slowly climb or get worse as you accerate and stay there until you let off the gas?

That is the type of knock to be worried about. The back fires from my exhaust when I would lay off the gas would create sparks of false knock. I wasnt worried about that.

Knock retard is just pulling degrees of timing until the knocking sensors stop hearing the unusual noise.

If you ever see a degree or two of knock try for sh*ts and giggles a bit of 100 octane to see if that cures it, if it doesnt it may just be false knock.

Another thing to point out is if you see 0 degrees of knock all the time thats not neccesarily a good thing. I usually advance the timing until I see knock and then I stop.... I like to see a degree or two so I know I am at the max of what my motor can handle. Just so that there is not any unused power.

Get it?
cool that was a great explaination, I never fully understood it, now i do.
 

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DOG
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Ok, I'm going to chime in here as well.

The goal is 0 knock retard on 90% of the WOT runs. Anywhere with more than 1 degree of KR at WOT is bad, particularly if its a repeating event.

KR down low isn't as bad an event particularly if it is under 1 degree.

The idea is to take the timing right to the edge of ping and then bring it back just a hair. 3 to 5 tenths is NOT going to get you that much more power, at most we are talking 2-3 ponies on a good day. However, it does you no good to get that little extra, when 20-30% of the time you get 1 degree KR events. You'd be better off consistently having 26 degrees of timing, then having 26.5 half the time and 25.5 the other half. Honestly, you'll do much better when you tune your timing tables for that goal.

Also, and this is a big thing that a lot of people forget, the engine will take more timing once you past peak torque. You're timing curve should peak around 24-30 rpms, decrease going into 4800-5200 and increase after that.
 

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Best Car Under $45k Period.
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Discussion Starter #5
THANKS BLITZ and EVERYONE! I get a little knock retard when letting off the throttle (around corners or just straight) or sometimes when it's switching gears.

I am STILL having a problem when I gun it hard (almost WOT), where the car does not GO ANYWHERE and the rev's skyrocket to 6000. A few seconds later (if I do not let off the gas) the tires squeel a little and then it shifts into a higher gear.

Where, this would be where I would need to get some good passing power and it would upshift and take off. Now it does this ^ even in stock form.

I guess I need to see the dealer :(
 

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May I quote you on that?
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It would seem like false knock might be a bit of an issue on the LS1. Otherwise, why would they have gone to all the trouble to relocate the sensors on the LS2?
 
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