Kezz,
Had to set my ignition up last night and changed my mind about your question re timing
So your ignition is like the CR750 motor, the Honda CR750 factory spec was 35 deg fixed no advance 11:1+ CR race fuel
The standard Honda cb 750 is static around 5 deg then 35 deg advance for total 40 deg 9:1, standard gas
Our engines are similiar so I have set my base advance at 10 deg static , all in at 36 deg by 2,500 rpm
With the power arc system you have 4 curves and I have set the other 3 curves up for totals 38 deg, 40 deg, 44deg. for some experimentation
Your comp ratio is a bit higher at 12:1 so what gas you using ?
Bear ; when I done a comp test after Melt down the other 3 cylinders were 160, 155,160. The 155 psi had a folded oil ring rail , apparently it doesnt seem to effect things dramatically , other blokes have said to me they dont worry about the folded rails anymore as it has minimal effect with very slight oil usage and no comp loss , just stuffs the bore , but for one off racing everybody at the high end just do it ?