I had 30MKI hull no. 45 If your boom has not been raised, there may a pretty steep angle for a boom vang. The previous owner of my boat raced it extensively and did well without one.
I never seemed to need one but I did have the traveller moved to just aft of the companionway and would sometimes rig a preventer to the toe rail on a run and that would bring the boom down. Rob
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