INLET /carb HELP WANTED

[dublin22]

Im racing a 1245cc micra on dirt.we can use a single choke carb on a micra inlet.the inlet can be designed or made how we want whatever carb we use must run through a 32mm restictor plate.the carb must be single choke.a swan neck is allowed.does anybody have any ideas on design ,what type of carb to use ect to give me the max performance. we only use first and 2nd gear,
your thoughts -knowledge much appreciated.
is there anyone out there that makes such things ?
andrew.griffiths@ntlworld.com