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hi guys, just finishing up the end of my cc503 install and am wondering if i need a LT4 knock module/sensor? i have seen alot of people have that in there sig that have this cam swap or any cam swap really. i am running the comp cam ultra gold (#19005-16)1.6rr so im expecting some chatter out of those, is that the only determining factor here, noisey rockers? if i need one, where do they have them besides chevy that wont be $200 or more? thanks
 

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you know what, every time i used roller rockers before, i threw in an LT4 knock module without question.

but on this build, with a fairly steep cam lobe, cc915 springs, and aluminum full roller rockers, i decided to just datalog and hope for the best..

and you know what, even though it's noisy as hell, it produces NO false knock

i even went to the extent of dumping a ton of timing into it to make it knock to make sure the sensor was working, and it is

so i'd say datalog it first, then buy the module if necessary
 

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Thats good news!
 

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i just saw some on summit, now they're out too. this stuff is getting hard to find!

luckily tons of modded LT1s have an LT4 knock module in them already, and they never fail, so eventually there will be a good supply of used ones out there.
 

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i just saw some on summit, now they're out too. this stuff is getting hard to find!

luckily tons of modded LT1s have an LT4 knock module in them already, and they never fail, so eventually there will be a good supply of used ones out there.
Luckily I wont need one.....I hope;)
 

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I have a cc503, with stock knock sensor. no problems ever
 

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I have a cc503, with stock knock sensor. no problems ever
Thats good news to hear.....I think its the roller rocker that make all the noise and throw things out, but I see where you have those and no problems so very good
 

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You can use the stock module/sensors and have them adjust for the rockers be desensitizing the knock sensors slightly in a mail order tune with tweaks for the cam timing injectors and 160 tstat.
 

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You can use the stock module/sensors and have them adjust for the rockers be desensitizing the knock sensors slightly in a mail order tune with tweaks for the cam timing injectors and 160 tstat.
Really. ..good to know im sending my pcm off wednesday to lt1pcmtuning. I will have to see if he offers that option:)
 

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Really. ..good to know im sending my pcm off wednesday to lt1pcmtuning. I will have to see if he offers that option:)
yes they will have an option for this, if its not included already...

either way I dont think you will have any problems regarding excessive knock counts...

roller rockers with roller tips if they are self align they are usually a bit louder, but nothing to really be concerned about if your rockers are adjusted properly.

non self align rockers with roller tips are they tick less due to the guide plates.

talk to this guys about your concern with excessive knock counts.
ive seen they place a small resistance but i dont have a clue if you will need to change the knock sensor.... probably they will know more about this :)
 

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You can use the stock module/sensors and have them adjust for the rockers be desensitizing the knock sensors slightly in a mail order tune with tweaks for the cam timing injectors and 160 tstat.
the knock module is a hard-wired thing that basically turns the knock sensor signal into a 'there has been a knock' signal, so unfortunately you can't adjust anything about how knock is detected in the ECM, that's beyond software control

the only thing you can really adjust is the amount of timing that a knock count will remove.

this helps deal with actual light detonation with aggressive timing tables in more controlled conditions, as you're only removing the amount of timing that the tuner thinks is appropriate. when a knock happens, it doesn't act as aggressively, you haven't lost as much performance.

this does not help much with false knock, as the knock will always be there and it will always pull timing, unless you completely tune out the knock sensor, which would be dumb.

thing is, if you have a decent amount of false knock, you've basically thrown the knock sensor idea out the window anyway. it'll always be at max knock retard.

even worse, if the tuner says 'ok lets retard only a little bit of timing because there's false knock'. the timing retards. then there's a real knock despite that minimal timing retard. the ecm has already retarded as much timing as the tuner has allowed, and the ecm can no longer fix the timing error, resulting in detonation.
 

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ive seen they place a small resistance but i dont have a clue if you will need to change the knock sensor.... probably they will know more about this :)
that is only for OBD-II to OBD-I conversions
 

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Discussion Starter #19
the knock module is a hard-wired thing that basically turns the knock sensor signal into a 'there has been a knock' signal, so unfortunately you can't adjust anything about how knock is detected in the ECM, that's beyond software control

the only thing you can really adjust is the amount of timing that a knock count will remove.

this helps deal with actual light detonation with aggressive timing tables in more controlled conditions, as you're only removing the amount of timing that the tuner thinks is appropriate. when a knock happens, it doesn't act as aggressively, you haven't lost as much performance.

this does not help much with false knock, as the knock will always be there and it will always pull timing, unless you completely tune out the knock sensor, which would be dumb.

thing is, if you have a decent amount of false knock, you've basically thrown the knock sensor idea out the window anyway. it'll always be at max knock retard.

even worse, if the tuner says 'ok lets retard only a little bit of timing because there's false knock'. the timing retards. then there's a real knock despite that minimal timing retard. the ecm has already retarded as much timing as the tuner has allowed, and the ecm can no longer fix the timing error, resulting in detonation.
so really nothing you can do....even with switching to the lt4 module?
 

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Realize you have a different year than mine the information is good.


http://www.go-fast.org/z28/diagnostics.html#knock

My 93 I cannot use LT4 module it is different than others the trick is to use resistors to desensitize the sensors inline or in the tune.

Post#9
does a 93 z28 have a knock module - CamaroZ28.Com Message Board

False knock


Another tip for the air intake temp sensor is to relocate it closer to the air filter just make extensions for the wires and make a place to install closer to
the air filter in the intake instead of the elbow less heat soak cooler temps less timing pulled.
 
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