John,

I don't wish to change the direction of this thread to discuss knock detection, but, I had also considered using a uC for this, however, how long does a 'knock' last? will the sample rate ever be fast enough to ensure capturing the peak?

I suppose analysing a knock link is a good way to get some further info but I would have though that understanding how the std ECU reacts to different levels of knock would be more useful if you want to know how to integrate it into a Boost/Ignition 'optimiser'.

Keep up the good work.

Andrew...

 

http://home.netcom.com/~bsundahl/kno...nockSounds.htm
16ms on the top picture - they are the backslash \ light blue strokes at 6KHz.

The Atmel 90S4433 runs at 8 MIPS and has an ADC conversion time of 65-260uS. I'll have a look at the signal processing that the Knocklink does at some point.

No worry about going off topic - this is entirely on-topic!

[Edited by john banks - 3/14/2002 3:09:01 PM]

 

You could get an A'PEXi Power FC and fine tune it, would display knock and other ECU info...

 

Spoils the fun though - I want to learn to do it myself

 

You CAN do it yourself with the FC!

 

No I mean design and build the circuits as well. It's a "hobby".

Like this one which is an EBC:


[Edited by john banks - 3/14/2002 5:26:38 PM]

 

John

What's the status of your EBC ? Do you have it up and running yet ?

Need a test dummy ?

 

I have a loom to which I can attach a working example, but it doesn't use RPM mapping yet. I've been thinking about your WI knock trigger - will post new thread on that

 

Evo Andy

Thanks for those fuel calcs, that seems to tie up nicely with my actual test results
One thing I have become more aware of is fuel surge, from 1/3 tank down I'm getting fuel pressure fluctuations (which I have no safety margin for)
Time for fuel system mods to fit a surge tank I think.

cc