big engine help

hi ive posted along time ago in engine bit no replies so thought i would try in here,
Hi got a pair of twin carbs on a 16v mk2 engine, 1st start of the day takes 3 /4 attempts all most like its filling the carbs again how do i combat that? nextwhen i get to about 2500/3000 revs in 3rd 4th 5th it splutters till 3000 and speeds off again i need basically keep the revs up,it was only tuned in feb before i got it and not sure if he was going to use it as a track car any thought? its got high lift cams and i was told they all cant be adjusted? cheers for any help matt