MG Car Repair: 77 Midget 1500 stumbles at higher rpm, spark plug wires, vacuum leaks

Question
I have a 77 Midget 1500 that stumbles and dies unless I let off the throttle and baby it at about 2200-2500 rpm. Just put on a used Weber downdraft DGV, manual choke carb. I went through Weber setup carefully. Checked for vacuum leaks. Compression test in cyl. 1-4 is 120,120, 115, 125. Pulled distributor and cleaned and reset the Crane-Allison electronic XR700 ignition. No vacuum attached, only mechanical advance, but it works correctly, advancing rotor about 10 degrees at full advance.  Attached full 12 volts to positive side of coil, not the 8 volts through the wiring harness.  Re-timed at 10 BTDC.  Just can't get it to rev to higher rpms.  Coil or spark plug wires?  Thanks for ideas.

Answer
Hi Tom,
To test if it is fuel related get a can of starting fluid and when opening the throttle and it would not want to rev up spray starting fluid into the intake as an extra fuel. If you are able to get a better rev up with the starting fuel then it for sure is the Weber at fault. If starting fluid does not help then you have another issue. By the way, your compression test is not great. Did you hold the throttle open during the tests? and hold the starter engaged for at least 4 or 5 revolutions?
What method did you check for vacuum leaks? Did you do a manifold vacuum test? If so what reading did you get. Did you test for exhaust back pressure? if so what readings did you get?
Howard