[Budweis]

prob just the choke kicking in did you try kicking it down? as long as was idling and running good before and you tightened distributor down tight it shouldnt be the timing. check your choke adjustments and if doesnt kick down once warmed up then adjust the idle. how high is very high rpm when starting? if roaring then look and see whats makeing the throttle move when you start it. and dont run it like that till you get figured out. what kind of carb you got?