Knock sensor on dyno

[Bruce Plecan]

If, I were going to do something like this, I'd just grab a couple sensors
from like a 4-6-8  Gm, then Chyrler, product line.  Then just setup a little
Op-Amp and wire that to a comparator to turn on a LED.   Use an ajustable
threshold on comparator to tune out back ground noise.
  If mounted in head parrarel with rod travel, if from side of cylinder
right angle to rod travel seems to be about the logic in mounting from what
I've seen.  Securely mounted being the buzz word here.
  You might even try the stock ESC of the matching year application (there
are several very different KS from gm), so they match the ESC module...
  If the EPA was breathing down my back, I would probably get real anal
about being dead on for frequency.  But for DIY_EFI, I think the above is
close enough.
  Just remember free advise is just that..... No guarantees


| > Knock Sensor on Dyno
| > I am currently building a eddy current dynamometer for testing small
engines
| > up to 70 ft lbs of torque. I am working on the instrumentation now and I
was
| > reading the archive and started thinking about knock sensing.
| > like to use a sensor out of the junkyard to keep costs down so any ideas
of
| > which one would suit me the best (partial to GM parts)?
| The one problem that comes to mind if you were using the GM knock sensors
| is the sonic qualities of knocking in your small engine. From what I've
| read, the knock sensor is tuned to specifically hear+amplify the
| characteristic knock sound for that bore diameter, and block. GM has had
| several different knock sensors, and even had a different one for the LT1
| and LT4, even though they have the same dimensions (LT4 was supposedly a
| little noisier). If you have the same bore, then I guess the knock would
| sound similar.
| > Can I put the sensor
| > in some type of holder then bolt it to the block for testing?
| I think as long as the sensor is in contact with the cooling jacket water,
| you should be OK. HTH!
| Andris/SPD