LT1-LT4 Modifications 1993-97 Gen II Small Block V8

LT4 knock module questions

Thread Tools
 
Search this Thread
 
Old May 18, 2012 | 12:08 AM
  #1  
93z383's Avatar
Thread Starter
Launching!
iTrader: (-1)
 
Joined: Mar 2012
Posts: 266
Likes: 0
From: Milwaukee, Wisconsin
Default LT4 knock module questions

1 - Is the false knock something that can be fixed with tuning, or would a LT4 KM then be necessary?

2 - Do I need one? FULL (I mean full) bolt on 97 z28 with LT headers, 3" Y, SLP LM1 catback. No rr's yet, but they will be done soon.

3 - If I do need one, where is the cheapest place to buy one? I'm seeing an average of around 75-80$ online everywhere I look, I remember they used to only be like 30 bucks lol...
Reply
Old May 18, 2012 | 01:53 AM
  #2  
Z28Camaro30Ann's Avatar
12 Second Club
iTrader: (15)
 
Joined: Mar 2007
Posts: 1,928
Likes: 0
From: Cheyenne, Wy
Default

False knock CAN be tuned out however you may sacrifice potential performance by changing the timing to eliminate the knock. The LT4 Knock Module is less sensitive and allows for more timing with less of a chance for false knock therefore you may be able to squeeze out a little bit more power or performance.

We can not tell if you "NEED" an LT4 KM b your mods. Some people will say yes, others no. In MY opinion, you only NEED an LT4 KM if you are getting false knock while tuning the car. If your tuner gets it right here he wants it and there is no knock, then there is no real need for the LT4 KM.

My SS had Heads/Cam/Intake/Exhaust and was dishing out 411 RWHP with 390 RWTQ. I had a stock LT1 KM on the car and NEVER saw a SINGLE BIT of knock at ANY point during the street and dyno tunes or during track datalogs. There is nothing wrong with getting one to be safe, but the NEED for one is determined when you start tuning.

They are not so cheap anymore because they are hard to find and getting harder. 75-80 is the going rate right now unless you find someone ditching one cheap. Good luck.

I hope this answers all of your questions.
Reply
Old May 18, 2012 | 03:22 AM
  #3  
93z383's Avatar
Thread Starter
Launching!
iTrader: (-1)
 
Joined: Mar 2012
Posts: 266
Likes: 0
From: Milwaukee, Wisconsin
Default

Thanks for a great answer I appreciate it!

That's exactly what I needed to know - if the tuner can see knock/false knock happening so I'll know if I need it or not. I don't think I will (I hope) but with the LT headers and loud *** LM1 I didn't know if guys have experienced that before.
Reply
Old May 18, 2012 | 07:28 AM
  #4  
Adam1203's Avatar
TECH Enthusiast
iTrader: (5)
 
Joined: Jul 2009
Posts: 548
Likes: 7
Default

Originally Posted by Z28Camaro30Ann
False knock CAN be tuned out however you may sacrifice potential performance by changing the timing to eliminate the knock. The LT4 Knock Module is less sensitive and allows for more timing with less of a chance for false knock therefore you may be able to squeeze out a little bit more power or performance.

We can not tell if you "NEED" an LT4 KM b your mods. Some people will say yes, others no. In MY opinion, you only NEED an LT4 KM if you are getting false knock while tuning the car. If your tuner gets it right here he wants it and there is no knock, then there is no real need for the LT4 KM.

My SS had Heads/Cam/Intake/Exhaust and was dishing out 411 RWHP with 390 RWTQ. I had a stock LT1 KM on the car and NEVER saw a SINGLE BIT of knock at ANY point during the street and dyno tunes or during track datalogs. There is nothing wrong with getting one to be safe, but the NEED for one is determined when you start tuning.

They are not so cheap anymore because they are hard to find and getting harder. 75-80 is the going rate right now unless you find someone ditching one cheap. Good luck.

I hope this answers all of your questions.
it really doesn't have to do with tuning though. It has to do with roller rockers. Its not designed to be less sensitive its designed to filer out other tones like those of roller rockers since the lt4 came with them from the factory.
Reply
Old May 18, 2012 | 07:54 AM
  #5  
Z28Camaro30Ann's Avatar
12 Second Club
iTrader: (15)
 
Joined: Mar 2007
Posts: 1,928
Likes: 0
From: Cheyenne, Wy
Default

Agreed Adam, but it is also less sensitive to the added noise you get from adding say long tube headers. The STOCK reason was for the roller rockers, but the reason LT1 guys switch to the LT4 is mainly for tuning and to prevent false readings due to interference from RR's, Headers, etc. We can squeeze a little bit more out of the motor with the LT4 module vs the LT1 module because false knock is less likely so the PCM doesnt automatically retard or advance timing on us. If there is no knock at WOT during the tuning process, no LT4 Module is necessary.
Reply
Old May 18, 2012 | 08:22 AM
  #6  
ahritchie's Avatar
TECH Addict
iTrader: (1)
 
Joined: May 2010
Posts: 2,241
Likes: 1
From: Charlotte NC
Default

I put in a LT4 Knock module when I did my first cam swap (with Roller rockers of course) My reasoning is GM designed it for roller rocker equipped LT4's for a reason (to be less sensitive to "noisy" RR's)....they have a lot more engineering resources and research capability than any aftermarket company and or tuner so I trust their choice to desensitize it. If the LT1 knock module was "ok" and not causing false knock why wouldn't GM "tune" the PCM from the factory and use the same old LT1 km on the LT4
Reply
Old May 18, 2012 | 01:07 PM
  #7  
Jazz-LT1's Avatar
TECH Apprentice
iTrader: (2)
 
Joined: Aug 2009
Posts: 351
Likes: 4
From: Hampton Roads, VA
Default

I look at it this way, it's so cheap why even ask the question... Just install it.
Reply
Old May 20, 2012 | 05:22 PM
  #8  
93z383's Avatar
Thread Starter
Launching!
iTrader: (-1)
 
Joined: Mar 2012
Posts: 266
Likes: 0
From: Milwaukee, Wisconsin
Default

Originally Posted by Jazz-LT1
I look at it this way, it's so cheap why even ask the question... Just install it.
Because I've spent probably 2 grand on this car in the last week So if I need it, sure I'll pick it up it's cheap, but if I don't, that's 80 bucks well spent on something else. Hell I got my gears installed for 100 lol.

Guess I'll find out when I get my tune done, that was my main question. Thanks for the good answers guys.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 03:15 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE