MG Car Repair: Car learches, stromberg carburetor, vacuum leaks

Question
I have a 78 mg midget seems to be running very nice how ever after i drive it for a little bit ie it gets warmed up if im just holding the speed or at low rpm moving the car seems to learch a little but if i give it more gas or take it on the high way or highway speeds it goes away. Im trying to figure out if this is a fuel/spark miss problem or is it in the trannie? More so how can i narrow it down to find out?

Answer
Hi Steve,
Lurching at light throttle settings just tells you you need to run some tests.
Compression test first. 125 to 180 PSI with little difference between cylinders and be sure to hold the throttle open when testing. If the compression is low on any cylinder adjust the valve clearance and test again.

Set the timing to factory specs and clean or replace the plugs.

The 78 Midget has a single Stromberg carburetor and is set lean. Lurching at light throttle setting is a sign of a lean condition so after all the above is complete you should try to richen the mixture a little as a test. If you have the adjustable needle you can turn the 3mm Allen adjustment down at least one full turn for a test. Also check for vacuum leaks.
Howard