Altering Ignition Timing via CAS signal manipulation

[David A. Cooley]

At 03:32 PM 5/7/99 -0700, you wrote:
>Well, the title should explain what I'd like to accomplish.  I would
>like to manipulate the electrical signal coming off of my crankshaft
>angle sensor to affect a change in my ignition timing from what the ECU
>would normally have it offer.
>
>My 98 Subaru Legacy 2.2 Liter has a magnetic crank angle sensor.  This
>is called a Hall Effect Sensor, right?  Anyway, it reads one or more
>rotating protrusions of metal on the crank shaft pulley.
>
>I am assuming that all four spark plugs fire each time a given cylinder
>charge ignites.  So I am assuming that if I delay the signal by, for
>example, 99 percent of the time between pulses that I would be
>effectively advancing timing by 3.6 degrees since it would be firing .99
>x 360 degrees late.  Right?
>

Umm.. no.. If it uses DIS and has 2 coils, one plug fires for the
compression stroke while it's paired cyl (on the same coil) fires on exhaust.
If it has a seperate coil for each cyl, then it fires each individually,
same as if it had a distributor.

>If so, how can I build such a device and make it adjustable.  

What would you want this for anyway?  to adjust the spark, modify the code
in the chip.
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           David Cooley N5XMT           Internet: N5XMT at bellsouth.net
     Packet: N5XMT at KQ4LO.#INT.NC.USA.NA   T.A.P.R. Member #7068
   Sponges grow in the ocean... Wonder how deep it would be if they didn't?!
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