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Old Apr 12, 2005 | 06:49 AM
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From: Winston Salem NC
Default no knock

I know this is a weird ? but

what would cause an engine to not knock at wot?

It will at medium throttle but wont at wot so I
wouldnt think bad sensors

890mv showed about 10.8 afr while 850mv showed
around 13.6afr
both of these Ive pushed timing up to 39* and show no knock
or hear no knock
Ive heard best power is made 1.5* before knock but how do you know
optimum if you cant find the break point?

any ideas before I blow it up?
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Old Apr 12, 2005 | 07:01 AM
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You may need to check, at what tps or rpm your pe mode kicks in. It may need to be lowered to give more fuel at lower rpms.
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Old Apr 12, 2005 | 07:17 AM
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thats been taking care of from 90 stock to 60s 40s and 20s

hows that gonna affect showing 0 knock?
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Old Apr 12, 2005 | 09:06 AM
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Originally Posted by gamedawgx53
I know this is a weird ? but

what would cause an engine to not knock at wot?

It will at medium throttle but wont at wot so I
wouldnt think bad sensors

890mv showed about 10.8 afr while 850mv showed
around 13.6afr
both of these Ive pushed timing up to 39* and show no knock
or hear no knock
Ive heard best power is made 1.5* before knock but how do you know
optimum if you cant find the break point?

any ideas before I blow it up?

Not sure what your KS problem is, but this is where a dyno shines.. If you are on a steady state dyno you can slowly raise your timing until no further tq gain is achieved in a particular cell then set it to the lowest timing setting that achieved that gain and you are good..
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Old Apr 12, 2005 | 04:18 PM
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From: Shelby County, Al.
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Originally Posted by gamedawgx53
thats been taking care of from 90 stock to 60s 40s and 20s

hows that gonna affect showing 0 knock?
you said it dont knock at wot and itwill knock at medium throtle...i just meant add more fuel where it knocks
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Old Apr 12, 2005 | 09:35 PM
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Originally Posted by Flipper
Not sure what your KS problem is, but this is where a dyno shines.. If you are on a steady state dyno you can slowly raise your timing until no further tq gain is achieved in a particular cell then set it to the lowest timing setting that achieved that gain and you are good..
steady state dyno?
i see what youre saying and it seems like it would work

I may call around to see if I can find any this week
Is this what I ask if they have? steady state dyno?

if I cant find one, would it be best to just go to the regular dyno
get my afr right, and start about 26 and bump it up 2 at a time till it falls off?

can you see in any way where the KS problem may indicate
another problem?
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Old Apr 12, 2005 | 09:54 PM
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Originally Posted by TIRBRNR
you said it dont knock at wot and itwill knock at medium throtle...i just meant add more fuel where it knocks
yeah I see what you mean
if it was still 90% PE the kr could be caused by too much timing not enough fuel from not entering PE mode which fattens it up
...makes sense
Its only showing knock at low rpm high load which Ive fixed allready
and Im basically just using that to let everyone know that the knock sensors do work

my main question is why none
I mean 13.6 is lean 39* is high
seems like it would knock like hell
but it dont
dont hear none dont see none


but thanks for the replys
seems like alot of members would find this weird
since its the exact opposite of most peoples problems
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