GM Holden Ignition

[Adam Tate]

I own a Holden Commodore V6, which runs the same computer (I think) as most 
other GM vehicles. The way I understand it, is that only the MEMCAL gets 
changed for particluar vehicles.
        Anyway, my question is - Is there a way to adjust total ignition 
advance outside of the MEMCAL. My engine has minor mods such as bigger 
intake, free flow exhaust and slight compression increase. I wish to run a 
more volatile fuel (namely avgas - BP100 racing fuel) and adjust the 
ignition to suit. I already have an aftermarket PowerChip MEMCAL fitted 
which gives quite good power and torque increases. I'm not really after big 
power gains here, it's more of an experiment than anything.
        If reprogramming the MEMCAL is the only alternative, how easy is it 
to do? I realise special hardware is required, but what about software?
        Also, I realise the high lead content of avgas will damage my 
catalytic converter, but just quietly, mine has been taken out. Also I am 
prepared to sacrifice an oxygen sensor in the name of research (well fun 
really).

Any help is much appreciated.

Adam Tate.
[at at multiline.com.au]
http://www.multiline.com.au/~atate/index.html