then you need to add more washers to the heel bolt, to get down to 4000rpm, you need 4-5 grams of heel weight. should be the long bolt with 4 or 5 washers on the heel.
as for the broken off powervalve housing bolt, if its broken off, get the others out, is it sticking out any from the cylinder or broken off flush? if sticking out, apply heat from a map gas torch and use vise grips on stub to work back and forth. If flush you have no choice but to dril it out with very small drill bit, and its much easier to do while off the sled so it can be done without bit getting off bolt and ruining the threads in cylinder.