PIC's and EST on a GM for traction control

[Thomas Matthews]

This recent PIC thread has got me really interested in one of my
"pie in the sky" ideas.... Namely my dream of having traction
control in my old car... So here's my idea: PIC are available in
BASIC, so I can handle that (barely), what I would like to do is use
the PIC to compare inputs from front wheels and the rear wheels, and
when rear RPM is greater than front (by like 5-10 % or so, I could
see having to play with this too) output a signal to the EST filter
of a 747 or 165 ECM... Any thoughts? What does the knock sensor
output to the filter, and is it easily mimicked by a simple PIC? Any
thoughts on how fast the ECM could respond to a faked knock signal?
Or could I tap into the wires from the filter to the ECM and send
the ECM a direct signal from the PIC? 
Any comments?
Tom