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I am running a generation 1 small block 350 chevy engine with OSE12P. It has been up and running on my engine for quite a while after working out the bugs. I just do tweaks now and then. The ECU is from a 1986-89 Corvette. Originally a MAF sensor ECU here in the United States. I had a wiring harness that I got for free that was so bad I just rewired the whole harness for OSE12P. One thing I did not take the time to figure out is the knock sensor. The first issue is on the OSE12P wiring diagram the knock sensor pin is not labeled. So which pin to the ECU would the knock sensor go? The second and bigger issue is how to make a knock sensor work on a US GM ECU. The US '165' ECU and the Australian '808' ecu are similar but have small differences from what I can see the memcal ESC module is one of those differences. In the US our '165' ECU use an external ESC module to get and decode the information from the knock sensor and then send it to the ECU. It was not until the '730' US ECU came out in 1990 that the ESC module was integrated into the memcal. The knock sensors on the later 90-92 vehicles are different than the 1986-89 '165' ECU. Its also worth noting that the 305 vs 350 knock sensors are different on both ECUs. It seems your '808' ECU came with a integrated ESC module on the memcal. Based on that I have found the Austrialian knock sensor is 3.9k. The 1986-89 US '165' uses a 100k knock sensor with the external ESC module. The later 90-92 GM '730' ECU with an integrated ESC module on the memcal uses a 3.9k sensor. I believe that if I had a v8 350 Austrialian memcal with integrated ESC module and a 90-92 350 US knock sensor this might work.

OSE12P Wiring Diagram: viewtopic.php?f=27&t=356

US GM TPI Knock Sensor Info: http://chevythunder.com/fuel%20injectio ... pg%20B.htm

Extra Knock Sensor Info: https://www.eecis.udel.edu/~davis/z28/e ... /165KS.txt

Have a look at the wiring in the text file in the ose12p zip file. Knock sensor is on B11.

Im not sure the ohms but if its the same values the sensors should be the same. The hardest bit will be finding the right knock board. Here only the HSV models have them. We've determined that the V8 ones start with a 1F code, but they are rare as they were not standard fitment. See "How can I identify a knock filter?" In the FAW (link near top right).

I found the FAQ page for identifying the knock filter below. Being from the US I dont really know the holden commodors unfortunately. Based on the OSE12P compatibility it says VN, VP, VR, and VS holdens have the '808' ecu. My guess is that the holden HSV is like a higher tier model of the commodor much like in the states we have a z28 camaro vs a base model. From what I can see the 5.0L engine is the largest engine the commodors got. The HSV model must be the one that got the v8? Another issue could be using a 5.0L Commodor ESC module with a US 5.7L knock sensor. I could see a 5.0L Commodor ESC module working with a US 5.0L knock sensor though.

Identifying Knock Filter: https://pcmhacking.net/forums/viewt ... =20#p13685
Holden Commodor Wiki: https://en.wikipedia.org/wiki/Holden_Co ... 80%931991)

You can use the external knock filter that you have but it goes in a different pin I think I'll see if I can find the info but I would have at a guess use the same pin as the USA maf tune used

Pin b7

That is a little surprising. OSE12P has the code to use a knock sensor on two different pins? B11 if you are running an internal knock filter on your memcal. B7 if your running an external knock filter? I think I may have came up with a solution to the memcal issue. The US '165' and '730' ecu are different computers. The '165 is a MAF ecu and the '730' is a MAP ecu. Well apparently the memcals are swapable if your reprogram the chip on it. So if I used a '730' memcal I could use the internal knock filter on the memcal along with a 90-92 5.7L camaro, firebird, or corvette knock sensor. If OSE12P was programmed to use both external and internal knock filters on both pins having two separate solutions would not be a bad thing I just want to verify first.

Watching with interest.
PS. HSV started out as a works engineering remanufacturer.Buying stock commodores from holden and working them. One of the things they did was stroking the 304 out to a 5.7/355. These were the ones with knock boards on the memcal. HSV vehicles were individually numbered in runs from 1 to approx 500. Low numbers, and are rare as rocking horse shad these days. But I understand from the gearhead efi spreadsheet there were heaps of american memcals for 5.7's. Look here http://www.gearhead-efi.com/BCCFind/ match engine OR bore size of engine and cyl count and you'll have several options for knock board.143 results from 90-92 .pm me If you need help.

I think the duel knock inputs isnt to do with software pin b7 is just hardwired to the same place as the memcal knock filter output pin on the memcal header both feeding the same pin on the chip that handles knock so b7 couldn't be repurposed as another extra input so just remains as external knock filter input.one of the guys on here built an adjustable knock filter and used b7 to input it to the ecu

Hmm that is interesting. If this is not software based then that would make sense. If the pins B7 and B11 both connect back to the same memcal pins for the knock filter technically I would think you could hook up two knock sensors. One on each side of the block like newer engines. Run one knock sensor to B7 and one to B11 if they are the same OHM rating then I would not think it would matter. If either sensor detected knock it would go back to the same place on the ECU if delcowizzid is correct. I have never seen a diagram for the memcal pins before. So someone who knows a lot more than me would have to confirm that. However I do have a picture of a AUJP memcal. That is a common '730' ECU memcal. Not sure if that is of any help. To answer barana's question about us memcals. Below is a good list of 305/350 memcals we had here in the us by broadcast codes. Based also on what barana has said the Commodors with knock filters on the v8 memcals seem to be rare. They did not come on all v8 commodors is what I understand. So unlikely I would get my hands on one. Assuming the '730' memcal is wired the same as a '165' memcal which they look like they are at least based on pictures. Then as long as I use a matching knock sensor with the filter board and wire the knock sensor to B7 or B11 it should work.


US '730' ECU Broadcast Codes

http://chevythunder.com/prom_bcc_1990.htm
http://chevythunder.com/prom_bcc_1991.htm
http://chevythunder.com/prom_bcc_1992.htm

AUJP Memcal

B11 would be sensor into the filter (raw sensor data).
B7 would be the output of the filter into where ever it goes in the ECU (the filtered signal).

You couldn't use the 2 interchangeably