knock spectra

[Todd King]

     I've been having some false knock problems lately with my car and am 
     trying to find some research papers or similar that discusses/shows 
     the spectral signature of a "typical" knock event. I think that 
     detonation usually shows spikes at about 6KHz (and maybe 13KHz)? 
     Anyone know where to find useful data on the GM knock sensor of the 
     late 80's? I mean the sensor itself, but related info on the 
     processing module is welcome too. Thanks for any leads. I finally got 
     the car back together ('87 turbo Regal) a few weeks ago with a decent 
     set of ported production heads, 50lb MSD injectors and a shift 
     kit/converter. Turbo is still too small, intercooler is still 
     inadequate, car is still "heavy", and it was way off on the cal (pig 
     rich, with over 1000mv seen on the O2), but that's sort of expected 
     when you pull into the staging lanes for your first pass a week after 
     reassembly and you haven't even gotten a full wot test blast out of it 
     yet, or set the boost. It went a 12.2x at near 113mph (yuk- too much 
     fuel and timing retard...) with an awful 2 sec 60' time, through the 
     muffs. It was bogging hard out of the hole, and the knock detector was 
     beeping for most of the run (pulling timing- and power), even with 
     "low" boost and a tank full of C16. Fuel system fell on its face at 
     the top of 3rd too; not enough pump. It still needs cal work and is 
     currently way off performance-wise, but it'll get there eventually, 
     just needs patience... Hope the knock detector problem is not too hard 
     to sort out; I think that the new set of T&D roller rockers are the 
     lion's share of the problem (they're fairly "loud") but there is 
     something else amiss too. Others use these w/o problem though, but my 
     set required notching for pushrod clearance at lift as well as valve 
     cover grinding since they were hitting those too. Anyway I have a new 
     "windy" turbo ;-) on the way plus mondo front mount intercooler that 
     should liven things up a bit. Wish UPS would settle the strike as the 
     parts are currently off in the ozone somewhere... :-( I too can vouch 
     for the "Max Boost" book from BEGI; it's cheap and pretty good IMO.
     
     Todd       tking at scic.intel.com