newbie - 12p tune - Knock sensor not working...

[felsy]

ok just found this http://uprev.com/documentation/Knock%20 ... Device.pdf
and going by that article you could use a piezo factory knock sensor (instead of microphone) with a sound amlifier and earphones to listen for the knock.
has anyone tried this?

[SirGollum]

Is there any other way of getting a knock sensor expect for finding a HSV memcal ? I noticed that VL400's nvram board has a provision for the filter to be soldered to it..

[Holden202T]

yeah with a v8 its pretty much a matter of finding a hsv or similar one and that is not an easy task!

[felsy]

but you dont really need the knock board do you? isn't it only used so it can be tuned slightly more agressivly than a standard tune and a fail safe for running lower quality fuel. so just to tune it could you use a knock sensor (commodore vn-vr v6 and v8 have same part no. for sensor) and hook it up to a sound aplifier?
from what i have read the knock sensor is tuned to a certain freqency, unlike a conventional microphone that other people have been using?

[VL400]

The knock sensor is just a piezo microphone. The knock board is a bandpass filter tuned to a freq that is mainly dependant on bore size. This is why the knock board is different from V6 to V8 but the sensors are the same. The knock board outputs a digital on/off signal the ECU can interpret as knock or no knock.

The VS ecotec was the first commodore PCM that had high/low octane tables and actually based the final spark figure on knock so you could run different fuels more safely. The earlier PCMs just detect knock, pull some timing out and ramp it back in - wouldnt want to be constantly running like that as its a reactive measure to actual knocking that wont do the engine any favours long term.

[felsy]

yeah i know the board has a filter on it, but but doesnt the sensor only pick up freqency between something like 6000hz to 12000hz?? unlike a conventional microphone ~60hz to ~24000hz

[SirGollum]

Ive found this on ebay..

http://www.ebay.com.au/itm/HSV-HOLDEN-1 ... 1c1cc65df3

Considering the rarity, is that a fair price for that kit you think ? Personally I wouldn't be confident tuning the Spark stuff without some 'automatic' measures to detect my stuff up's

[VX L67 Getrag]

Thats fairly expensive, I managed to pick that kit up with instructions & pcm for I think $165 delivered, so you may be able to get it cheaper?

Others may have different ways too, but yeah unless you get the proper stuff & then you still have to fine tune the knock sensor sensitivity in the cal to make sure it's working correctly!

[VL400]

Also confirm it is in fact a V8 knock filter on the memcal, not sure about that particular ebay seller but there have been lots of V6 memcals sold as V8 ones on ebay. There is a good cross reference list here .. https://pcmhacking.net/forums/view ... =20#p13685

[vn5000]

You cant buy a new hsv memcal anymore .They have stopped making them.If someone tries to sell you one claiming it is brand new then your being ripped off.
Email that ebay seller and ask him if the knock filter board part no. starts with 1F. Ill bet it doesnt .
It will be a v6 knock board with a hsv calibration programmed onto the eprom.From my experience if you use a v6 board on a v8 you will get false triggering ,which will decrease performance.