Power loss since metering head change!!!!!

changed my mk1 gti meter head because oof mixture screw not adjusting.
got a k jet meering head of a mk2 gti head and injecters, now got it running notperfect but running once warm but on the road theres just no torque per say.

old meter head was pulling and running as a gti i should so mechanic said but with this new metering head struggles up hills, pulling of etc… any one has a idea on what could be causing it would be a great help.

had car 8 weeks and this only thing thats stopping me from taking it for a proper spin ( lack or performance ) tax motd and insured but not worth the run….. so close yet so far as they say

HELP!!!!

burbo

Hi

Have your checked the fueling to see if thats correct?  It could be over fueling or the timing/fueling was set correctly to the old metering head and now that you have changed that it will require setting up again.  

I'd put an air/fuel ratio gauge on the car to see what is happening and also stick a timing light on it just incase.

Andrew