Programmable digital knock filter?

[festy]

A module is on it's way down to 'VX for testing.
I can't do much on-car testing myself - I drive an old diesel, and the Alfa upsets the neighbors even at idle
Once any bugs are found and sorted, it will then take 3-4 weeks before they're ready.

[vlad01]

F**k the neighbors

[VX L67 Getrag]

Well I've had the module for a week or so & done a little bit of testing, still trying to get my head around which settings to choose to set it up!

I've managed to get the output to trigger on the dyno (attached grainy photo's) if you look on 1 of them you can see the blue LED lit up of the module, then on the MAIN screen of the dyno in the middle you can see HIGH KNOCK DETECT, then on the other image you can see where all the data is it has lit up red in the middle saying a figure of 194 & then there's a standard image of when it's just stock which sit's on 164-165!
All the numbers are irrelevant as I'm just using the map2 signal & seems the LED of the module triggers, then the main screen detects it & then the value on data screen!

If I can figure out how to upload a video to you tube I will put it on, but the images are just screen shots of it & pretty crap quality too!

[festy]

You were making much better progress than me, my first attempt to hook it up to my ECU crashed my laptop - and my second try stalled the engine and crashed the ECU
So I had a look at the 808's schematic to work out what I was doing wrong, and 3rd time lucky:

alfa_knock.png (19.39 KiB) Viewed 7954 times

I had the knock filter wound up to make sure it showed even the slightest bit of knock, and added heaps of timing until it started to ping

[antus]

Looks good!

[festy]

Never having logged a car with a knock sensor I wasn't real sure what it *should* look like, but when I compared the ignition advance and knock count history tables, there was a clear correlation between them so that was nice to see

The problem I had with hooking it into an 808 was that I had assumed because pin B7 is active low then it would have an internal pull-up, but it's actually pulled down by the ECU so needs an external pull-up.
Cliff Harris mentions the 165's B7 pin idles at around 9v, so the ESC module must pull the pin high.

This is a rough sketch of what I'm currently using - and yes that FET is way overkill, a 2N7002 would do the job just fine I imagine but it's what I had on hand...
The filter is set up in active high output mode, which translates to active low at the #KNOCK_B7 pin.
Does anyone see a problem with this setup?

knock_trigger.jpg (40.27 KiB) Viewed 7939 times

[The1]

awesome work festy and everyone, i missed this thread, if you need testing on various pcm's VS-VY i can do so on the bench, also have knock sensor input and trigger which i used for testing knock active loops in the enhanced bins, i can see this being handy for engines that arn't even efi.

[delcowizzid]

im gettings crazy ideas now of someone making the 808 into a full on chassis datalogger and having nothing at all to do with running an engine lol.measuring ride height on all four corners ,g's elapsed time etc

[festy]

im gettings crazy ideas now of someone making the 808 into a full on chassis datalogger and having nothing at all to do with running an engine lol.measuring ride height on all four corners ,g's elapsed time etc

I haven't got ride height (yet), but 3 axis G and lap times are already covered

[VX L67 Getrag]

WELL a BIG thanks to VL400 for helping with getting the data logged in TP!

It's hard to get it to capture KNOCK events that happen at less than 10ms when the PCM is only outputting the data to log at 70ms to 120ms!

But with Festy's help in setting up the correct procedure I'd definitely be relying on the knock module voltage sensing in these excel exports over the misleading factory knock detection!

I know the factory sensors can be dialed in but was just doing this as a pure test & LOOKS AMAZING!

For everyones info I could get another 8 deg's of timing in the timing on Impco LPG before getting det & I already had extra timing over factory petrol as I added the differences that the LPG spark map had in over the petrol spark map!

But the high det areas with low tps response were from the car being on petrol with the extra LPG spark & the extra 8 deg's!