Hesitates and holds back on light throttle/just after gear change etc

Is this just a low-comp/BD10 problem or should it drive as normal?????

Had injectors ultra sonically cleaned/re-conned over the winter,the base Co was 8% when I re-fitted them,set it to 3% and thats when its started this hesitating/holding back

Spec is:low-comp,BD10's,big valve ported/polished head,Stg3 MSD chip,
T34.63.

Thanks Kev