K'N cone or slip-in?... the cones breath way too much.... jetting will be more finicky...
... with a slip-in,... I'd go with a #150 main,... keep the pilot stock unless you need to turn the idle mix out more than 3 turns from full closed... with a cone, I'd start with a #152.5...
... and,.. based on Halvor's O2 tests... I'd try it with the stock spacer as well... ... if you notice any jerkyness at mid throttle, go to a 2/3 spacer ...
Keep in mind.... bigger jets don't make you faster,.. the correct jets do...
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