QwkTrip

iTrader: (23)

Bringing this thread back because subject is of interest to me. Can anybody verify that it actually works well to reprogram LS1 PCM for LS2 knock sensor? I know the idea is out there but I want evidence it works properly.

Can reprogramming be done with HP Tuner? That's what I have but I'm not familiar with it yet.

CalEditor@PCMCalibrators

iTrader: (4)

I can switch the type for you. I have never seen the setting in HPT

QwkTrip

iTrader: (23)

That is definitely peaking my interest and might provide the cleanest integration. Are there any drawbacks or loss of capability of a LS1 PCM that has been switched vs. the LS2 PCM made for the task?

I'm trying to figure out if it's a reasonable recreation of the LS2 technology or if the LS1 ECM has the identical capability but just not utilized in the Camaro. I'm not interested to do the switch myself (leave that to you) but I do want to understand what is done and how it behaves after the switch.

QwkTrip

iTrader: (23)

I have an iron block if that makes a difference. Use truck calibrations?

CalEditor@PCMCalibrators

iTrader: (4)

There are 2 types of KS currently being used:

• The broadband single wire sensor
  
• The flat response 2-wire sensor

Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The amplitude and frequency of this signal will vary constantly depending on the vibration level within the engine. Flat response and broadband KS signals are processed differently by the PCM. The major differences are outlined below:

• All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly fluctuating frequency and amplitude of the signal, will always be outside the bias voltage parameters. Another way to use the KS signals is for the PCM to learn the average normal noise output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise channel, in much the same way as the bias voltage type does. Both systems will constantly monitor the KS system for a signal that is not present or falls within the noise channel.
  
• The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is learned and output by the PCM. This noise channel is based upon the normal noise input from the KS and is known as background noise. As engine speed and load change, the noise channel upper and lower parameters will change to accommodate the KS signal, keeping the signal within the channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce spark advance until the knock is reduced. These sensors are monitored in much the same way as the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will not be present.

little more on the broadband single wire sensors
The PCM uses a KS in order to detect abnormal vibration in the engine, such as detonation, or spark knocking. Mounted in the engine block, the KS produces an AC signal at all engine speeds and loads. Next, the PCM adjusts the spark timing based on the amplitude, and on the frequency of the KS signal. The PCM calculates a normal level of engine noise, also known as the noise channel, from the KS signal. The noise channel consists of an upper and lower region. A normal KS signal should vary within the noise channel as shown in the Knock Sensor Signal - Normal. A KS signal outside the noise channel, as shown in Knock Sensor Signal - Knock Present, indicates spark knock. The PCM will then adjust the spark timing to eliminate the engine knock

Knock Sensor Signal - Normal

(1) Upper Noise Channel Region
(2) Noise Channel Average
(3) Knock Sensor Signal
(4) Lower Noise Channel Region


Knock Sensor Signal - Knock Present

(1) Upper Noise Channel Region
(2) Noise Channel Average
(3) Knock Sensor Signal
(4) Lower Noise Channel Region

01ssreda4

iTrader: (96)

I have an 07 aluminum 5.3 and I relocated stock LS1 knock sensors running off an LS1 computer to holes already in the side of the 07 block. What should the new settings in the tune be? (I know they have to be more sensitive based on location change).

QwkTrip

iTrader: (23)

Very well. Thank you.

I've been looking around and I still can't find anybody who has been successful tuning an engine this way. Lots of examples of engine not running right and going back to LS1 knock sensor. Can you point me to some board members that made it work?

CalEditor@PCMCalibrators

iTrader: (4)

We have been doing it for some time

TransAm-Z

iTrader: (39)

Do you have a sample tune you would be willing to share?

I have copied tables from a 4.3 litter, but I know the sensitivity tables are way off. I had an issue last summer with a run that was way too lean and the LS2 style knock sensors did pull timing, but not enough... Damaged 2 pistons.

Thanks!

maroonls1z

Hate to bring this tread back but no one ever answered to real question and im about to put an ls7 in the camaro and i would like to run the right knock sensors and a racetronix conversion harness. Has anyone made this work right? do you need to re-pin like mentioned earlier in this thread. Hitech Tunes told me it shouldnt be a problem switching it over but i want to make sure people have done it and are not having problems

soundengineer

iTrader: (16)

the LS2 style sensors will work....but you have to reprogram the sensor type in the tune, and you will have to wire one side of the sensor to a ground...
then you have to redo ALL of the knock tables...and its not a simple or easy task... lots of trial and error...

simpler to just stay with the stock LS1 one wire style sensors.
you can use the LS6 valley cover on an LS2 block with no issues.

neither sensor really works any better or any worse if tuned correctly...

Russ K

iTrader: (1)

LS2 knock sensors are wired with a signal & low reference and the LS1/6 only has a signal circuit. I just drill out & tap the stock knock sensor mounting hole to 10mm & use LS1 knock sensors.

Then I go to the Knock Sensor Global Gain table and multiply the entire table by .9 at at time to increase the knock sensor sensitivity until spark knock is seen with sensible spark timing, then increase the table by 5%.

And an LS6 valley cover will not fit on a LS2 block.

Russ Kemp

The highlander

bump!

The highlander

My guess and what we can do is to buy 2 of the 213-924 which are from the express van and copy the calibration over and sensitize accordingly. Repin the ECU apropriately. It could be done but you would need a keen ear or use the knock headsets to corroborate...

My concern is that the knock sensors and harness for the LS1 are extremely close to the headers.

maroonls1z

what would make the express van sensors better than lets say an ls7 sensor with a adapter harness? you can always wrap the header and harness if heat is a worry. Are the value for the 2 different types of sensors measured in the same units? Basically can you copy a factory file for that motor over and adjust from there? i know that forged internals leads to more noise and therefor would need different thresholds

The highlander

That the express van sensor has actually the data from a GM tune and it works rather well.. the only problem I ever saw was that it is located on the manifold or top side of bell housing.. can't really tell from the picture. but since the location is different the sensitivity should be all that is needed to be tuned... But the data for the sensor is there with the same tables... no conversion needed...

The LS2/3/7 knock sensors use different types of tables and might not be compatible with the express van/s10 data.

If you want to do this right you need the right approach and that is factory data with factory sensors with factory locations. Since not all 3 can be had at least factory data with the factory sensors can be used.

I doubt the racetronix conversion harness (which I have) works, since the pin to the ECU is different than the stock pins. Unless you only need to pin 2 wires, but I recall you need to repin all 4 wires (2/sensor).