Who uses knock sensors?
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Who uses knock sensors? Was reading a post from 2015 as tearing down my LM7 and adding a blower cam and probably a procharger. Will also be running true duals. The post said most people aren’t running then on the LS based engines because a cam change will cause issues unless your running a aftermarket ecu. I will be running a 411 pcm and stock LS1 harness my on 1994 z28. My original LT1 engine had a loudmouth with headers, ypipe, off-road pipe with a blower and 1.6rr and never had any knock issues with stock computer. But if I could do away with having two spend $100.00 for sensors and new harness as stock ones on this motor were worn out, that would be great and just use plugs.
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TECH Regular
Joined: Sep 2019
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Are you using stock ecu? Mine will just be a weekend warrior and not driven much so plug checking would be a easy idea. Did you buy a knock valley delete plate? Was wondering if I could just seal the holes up where the knock sensors were...
Stock Ecu...ls3 block with an ls3 valley cover. I tapped the holes on the side of the block and have ls1 knock sensors installed there, but decided not to use them and just read plugs. They aren't plugged in and changed knock sensor codes to no report.
Fuel used typically dictates whether or not you should. If you're running straight M1 or E85, the tuning window is so wide you just read plugs. If you're going to run straight 93/91 pump gas it's a good idea to keep the knock sensors active.
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Verdad Gallardo What is the gist of their stance, especially considering OEMs use them on anything with any power? Racecar stuff is a different story.
OP is going boosted. I've watched knock sensors save a motor from detonating to death during an overboost event due to a wastegate failure. Not everybody logs everytime the car goes WOT and knock sensors are cheap insurance.
Mostly this. The Real Tuners stuff is geared almost exclusively towards those who have an aftermarket ECU. In that case you have to get some type of a baseline and essentially go out and make the set up knock. I don't know too many people that want to go do that. It has been a few years since I listened to that specific episode so I don't remember all the details. A quick google search should bring stuff up though. The TurboBullet - Tech group on Facebook has a bunch of good info as well.
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When i put the 2.4 in my evo with the stock ecm it was seeing knock everywhere including idle. as i was reeling that part of the tune in, it pulled so much timing it backfired and bent my throttle body blade 
that said, i think they are a valuable sensor to take advantage of, you just need to get the settings right. i have my evo and corvette set up to tell me when it sees knock, so its mostly used to tell when i get a tank of gas that is a little off. unfortunately where i live now, thats far more common than a couple years ago.
that said, i think they are a valuable sensor to take advantage of, you just need to get the settings right. i have my evo and corvette set up to tell me when it sees knock, so its mostly used to tell when i get a tank of gas that is a little off. unfortunately where i live now, thats far more common than a couple years ago.
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From: Norn Iron
Mostly this. The Real Tuners stuff is geared almost exclusively towards those who have an aftermarket ECU. In that case you have to get some type of a baseline and essentially go out and make the set up knock. I don't know too many people that want to go do that. It has been a few years since I listened to that specific episode so I don't remember all the details. A quick google search should bring stuff up though. The TurboBullet - Tech group on Facebook has a bunch of good info as well.
GM would have to do the same go get the baseline in the OEM ecu, but of course, when you make the "noise" of an engine change...that baseline changes, and then the tuner would need to start that process again, although to a lesser degree as GM have already done most of the hard work.
I believe they are a good failsafe esp on boosted pump gas setups. You can increase the retard amount to a nice big number just in case. The factory settings are quite conservative.
I’ve also seen very strange behavior when the knock sensors are not present. System shows max KR and there are no sensors. So you need to get into the tables, there are a few, and tell them not to remove timing.
Drives me nuts when asked to tune an engine swap and the owner says he was told NB O2’s and knock sensors not needed.
Lastly, moving the LS1 etc knock sensors to the side of a Gen IV block works, but all bets are off because the calibration is out the window.
I’ve also seen very strange behavior when the knock sensors are not present. System shows max KR and there are no sensors. So you need to get into the tables, there are a few, and tell them not to remove timing.
Drives me nuts when asked to tune an engine swap and the owner says he was told NB O2’s and knock sensors not needed.
Lastly, moving the LS1 etc knock sensors to the side of a Gen IV block works, but all bets are off because the calibration is out the window.
I believe they are a good failsafe esp on boosted pump gas setups. You can increase the retard amount to a nice big number just in case. The factory settings are quite conservative.
I’ve also seen very strange behavior when the knock sensors are not present. System shows max KR and there are no sensors. So you need to get into the tables, there are a few, and tell them not to remove timing.
Drives me nuts when asked to tune an engine swap and the owner says he was told NB O2’s and knock sensors not needed.
Lastly, moving the LS1 etc knock sensors to the side of a Gen IV block works, but all bets are off because the calibration is out the window.
I’ve also seen very strange behavior when the knock sensors are not present. System shows max KR and there are no sensors. So you need to get into the tables, there are a few, and tell them not to remove timing.
Drives me nuts when asked to tune an engine swap and the owner says he was told NB O2’s and knock sensors not needed.
Lastly, moving the LS1 etc knock sensors to the side of a Gen IV block works, but all bets are off because the calibration is out the window.
Last edited by BCNUL8R; Nov 17, 2020 at 12:35 PM.