VW Scirocco GT2 1.8 carb running problems

[rumpelstiltskin]

Mate of mine has some problems with his Scirocco 1.8 GT2 Carb model.First problem is it needs the throttle down to start when hot,second problem is it will sometimes cut out when going down the gears,usually on a slight decline,generally the car feels underpowered!This has been driving him nuts and no garage has got to the bottom of it!Here's what he's had done to try and get to the bottom of it,deep breath...It has a replacement Weber freshly rebuilt with rebuild kit,new fuel pump,fuel filter,coil,plugs,leads,tappets done,alternator,rotor arm,dizzy cap,basically most things that would cause running problems!Anyone any ideas?Small reservoir between pump and carb has been cut out the equation too!