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knock detection dynamic ignition control
Has anyone experimented with converting a non-knock sensing VW/Audi
ignition system to a dynamic knock-sensing system?
I am interested in somehow defeating the sensing of boost-pressure and
possibly inlet air temperature and substituting some type of dynamic
ignition timing control instead. I already use a visual/audio knock sensor
to tell me what is happening inside the engine under varying conditions
so I should be able to do some experimenting without blowing things
apart and destroying pistons, rings and bearinsg, etc. I am running
an externally adjustable wastegate and a computer modified to
accept higher boost levels without shutting down the injection
system. A more aggressive advance curve is also part of the computer mod.
I can run ~~15-18 lbs of boost with no detonation problems at all
(using 92 octane fuel). This leads me to conclude that the computer is
dialing out much to much advance as a function of boost. I feel that I
need to reduce/eliminate the amount of advance that gets dialed-out as
a function of boost because I never reach a point where detonation
becomes a problem as I crank up the boost, the computer is over-
compensating because (I theorize) this boost/advance curve is optiomized
for the 87 octane fuel that was intended by the designers and not the
92/93/94 octane fuels that are now commercailly available. I am also
not getting the increase in performance that I would expect given the
greatly increased boost levels and am concluding that this lack of
performance increase is also due to overcompensation by the computer
with respect to ignition retard as a function of boost pressure.
Anyone have any ideas on this subject or know of any commercially
available systems that might fit my needs?