Chainsaw Repair

If I read that correctly you have 19 degrees of rotation from the ex opening until the transfers open .That would equate to 19 degrees of blow down not 23 .23 would be a lot better though .

You're going to have to put the math to it .You need the extra transfer area for sustained high speed runs .As the speed increase  the time for transfer decreases therefore you need more area and/or more time open . There's a ratio involved related to speed but I can't remember it off the top of my head .

You have to keep in mind a lot of folks use software that pretty well figures this stuff out .I do it the old fashion way with the degree wheel and a port map .--as well as a little blind luck .