ok guys done a lot to my gk76 sp2 ?? i know my stuff ?? but when i nail it it seems to go up in steps ?? not smooth ?? is it fuel starvasion ? no pump just vacume so it could be that >> or a dirty tank thats blocked or ??is it the TPS that alters the timming ( ing ) any one else seen this i know the fuelings crap but ive sorted that with new needles . oh it will also cut out when on tick over some times

ported head
440 kit
full make over any help thanks

when doing the needles did you change the dreaded O rings ? These cause overfuelling when engine hot causing the symtoms your desribe.

Also carb balance maybe required.