I don't know alot but i'll through my 2 cents in. The main jets should not have any real bearing on what your describing. It sounds like you need to balance your transfer slots on the primary and secondary to help get some more air in. You may need to get some holes into the plates but thats after the other things have been tried cause thats kinda permanent. Air bleed adjustment,idle feed restrictor sizing may also play in here. I would look where your primary plates are in relation to the transfer slot 1st though. Hope this helps.