I have a Disco 1 V8i 3.9L
What is involved to change it from mecanical advance timing to electronic advance?
It has a Dastec chip that controls fuel only and I want this to control timing as well for improved performance.:doh:

If I understand your question correctly you have a distributor and coil set up for your ignition. I'm not sure about your reference to a Dastec chip for fuel - I assume you mean your ecu has been chipped?

If you want your ignition timing to be fully electronic you need to change the whole engine management system and get rid of the distributor in which case you will need to change the timing cover, buy coil packs, and then there is the question of cam/crank sensors. I suspect it would be easier to buy a later Disco with Gems or Thor engine management.

I am sure somebody else will come along and either confirm what I suspect or be able to give you details of what is possible.