HI,

IF you have a access to a co% machine it a bit of piss, when i chip a rs turbo,
i take off the fuel presure actuator at the side of the fuel distributor(metering unit)
and then you see a brass screw, remove this and then you will see a allen key
which some are sensitive compared to others, turn in to increase co% a 1/4 of a turn and put
the thing back together, and reset co% 2.5%approx on idle then at cruise
fuelling approx 3500rpm the co should be up another 1% when you hold the revs
at 3500rpm for about 30 secs to 1minute, if to rich reset vice versa, bit messy
with fuel about so take care, and dont loose the seals off the pressure actuator. to run more than 15psi is your risk,unless you can have a power run to check fueling at 15plus, listen carefully when on boost for pinking
detonation.

DAVE R