thats what i was thinking hornet7 have had new plugs and leads but didnt gap them guess i best go pull them out and do that then, does certainly feel like ignition cut, comes on boost pulls well then cuts out and doesnt cut back in until you bring your foot back up off the throttle and then it takes around a second for it to pick up, dump valve is also rather late also when its picking back up....

Hmm....

Dave