Man you are a spead freak huh! I don't know of many people that could really give you any sound advice on what broadhead to shoot at those speeds. I don't know of any fixed position heads that would fly well at those speeds exspeacially with 4'' straight vanes.If you are dead set on using a fixed position broadhead you may want to consider a helical or at least blazer vanes,even then I would have to see it to believe it.GOOD LUCK!