In my experience of running these motors over years and having to build very many I have found you need at least ~80:1 (total) fuel to oil ratio at higher than stock power levels to reduce wear on critical parts in the engine *chamfering of apex seal biggest problem - see here >
http://www.riceracing.com.au/apex-seals.htm *. The oil metering pump is not of adequate supply, nor does it distribute lubricant very well either thus extra lubricant is required in the fuel.... if you want to ask me why that brand you can PM me or simply go to ausrotary.com and do a search where I have spoken and given examples at length on this topic.
Went for another drive this afternoon and the car is allot of fun, 3rd gear accelerates out so well, its almost pointless selecting it at 100kph cause when you over take you are changing gear in what seems just a couple of seconds... better to leave it in 4th! hahaha and I want to run 1.7bar eventually ! 
that seems silly now
I went through some old notes and a friend of mine in Norway has a S5 13b turbo with T66 turbo (similar to mine) 1.0 a/r rear turbine and on his bosses engine dyno with 1.7bar boost it made 580bhp using 98 Optimax and water injection....... they ran up to 1.9bar at mid range revs on the stock 9.0:1 compression ratio.
I think for this car 1.4kg/cm will be more than enough :lol: