LT4 Knock module vs. LT1 Knock Module
Thread Starter
Le Mans Master
Joined: Feb 2002
Posts: 7,858
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LT4 Knock module vs. LT1 Knock Module
Has anyone ever looked at the spark advance and retard tables in the PCM on an LT1 with LT4 ESC (Electronic Spark Control Module also called knock module) installed, vs. an LT1 with it's stock LT1 ESC installed?
I wonder if ALL the LT4 ESC does is just be more accurate in deciding what is true knock vs. false knock? I was wondering if it changes any of the spark advance or retard values in the PCM tables.
Anyone know?
P.S. referring to the chip that plugs into bottom of the PCM, not the knock sensors that plug into the either side of the block.
I wonder if ALL the LT4 ESC does is just be more accurate in deciding what is true knock vs. false knock? I was wondering if it changes any of the spark advance or retard values in the PCM tables.
Anyone know?
P.S. referring to the chip that plugs into bottom of the PCM, not the knock sensors that plug into the either side of the block.
Last edited by Lone Ranger; May 26, 2005 at 02:09 PM.
Pro
Joined: Nov 2004
Posts: 698
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From: louseyville Ky
I wish I could help you out. I am curious about this too. The only thing that I can "think" is that the Lt4 would be a little more forgiving than the Lt1 module. As stated above this is just a "thought". I will be interested to see what the masses have to say about all this. 
Safety Car
Joined: Apr 2003
Posts: 3,793
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From: VA
I was wondering if it changes any of the spark advance or retard values in the PCM tables.
I wonder if ALL the LT4 ESC does is just be more accurate in deciding what is true knock vs. false knock?
Intermediate
Joined: Oct 2004
Posts: 43
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From: Pittsburgh Pa
Originally Posted by steve9899
Installing the knock module does not reprogram your PCM, therefore there are no changes to the tables.
It is less sensitive. That may be more accurate or not depending on circumstances. I suppose there might be cases where the LT4 KM ignored real knock that the LT1 would pick up.
It is less sensitive. That may be more accurate or not depending on circumstances. I suppose there might be cases where the LT4 KM ignored real knock that the LT1 would pick up.
I talked to Ed Wright of "FASTCHIPS" about this subject. The LT4esc DOESNOT affect the the spark advance tables. But, . . .I did a test at the track with both esc's , and what i experienced was very suprising! my car (which is a lt1) actually ran better with the lt1 esc . When i ran the lt4 esc , for some really strange reason that no one has been able to answer for me , my car lost 4mph at the 1/8 mile and 7mph at the 1/4 mile . I did 2 runs with both esc's and both times the lt1 esc had my car performing much better . I dont know why that happened and i am very suprised about it , and would really like to find out why.. . . does anyone know????
Large Impressive Member
Joined: Jul 2003
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
From all I've ever read on the subject, The LT1 KM was just too sensitive to begin with. Add headers, roller rockers, etc. and the LT4 module becomes a necessity to extract full performance. I had an LT4 KM in my original short block when I had a bearing problem and believe me, it did it's job. It derated the engine so much that it wouldn't pull a greased string out of a cat's a$$!
