Some time ago I replaced all the hose and fittings in my fuel system, at the same time replacing the standard CAV fuel filter assembly with a Racor 120AT. See here (http://www.bavariayacht.info/forum/index.php/topic,503.msg4265.html#msg4265) for my parts list.
At the time I fitted the 120AT there was some discussion regarding its throughput of 57 litres per hour with a 2 litre Volvo Penta MD22P-B. The calculations I did said it should be OK. However, I note in the Racor 120 Series Brochure (http://www.parker.com/literature/Racor/Racor_Fuel_Filtration_-_120-Series-FFWS_-_RSL0161.pdf) that there is a 120B model, with a higher throughput of 76 litres per hour. I've just heard back from Racor:
The 120A can be fitted with the filters for the 120B. The part numbers for the filters are R13x (instead of R12x on the A series):
R13S (Brown) is 2 micron filtration
R13T (Blue) is 10 micron filtration*
R13P (Red) is 30 micron filtration
* Same as on my Racor 120AT, R12T