I spoke to the guy who built mine, and re-built it in '99. Unfortunately Janspeed no longer have any of the original build specs for their conversions. They were bought out in 2000 and all the build info went then.
The standard turbo conversion runs at 7psi, mine should run a touch more but I've got the boost backed off at the moment. As far as I know timing, mixture etc should be set at standard - the zytec box takes over from there. Oil, I use a decent 10-40 semi-synth and it seems happy enough (Mine is also a Wood and Pickett converted car so it has extra instrumentation). Mine uses different plugs from standard, but I can't remember what they are.
If you do manage to get any info, could you please forward it on to me. No-one seems to know anything about these cars and there aren't many left at all. Lots of them had the turbo installations removed in the early '90s because of difficulties with parts (and pistons). The Rotomaster turbo is now serviced by Garrett which makes life easier. The turbo Janspeed used appears to be a marine one, mine was replaced after the housing cracked. Not cheap.
