It's the amount of mechanical advance - in distributer degrees - which are doubled for engine degrees! So - if it says '9' for example - then that means 18 degrees advance is available from the bob-weights.
Hmm - in the dizzy there should be alittle plate with a 'finger' - under that - are the two bob-weights. Usually the finger just has a number on it. Maybe it is the R9 - but I don't think so. Doesn't matter - I just wondered what advance was spec for the 803 engine.