All good advice so far.

One thing that I would also check is the Vacuum advance system.  I had a similar problem with my 84 California model even after giving it a tune up, sputtery acceleration at best.  Then i decided to take my vacuum tester to the vacuum advance system and the hoses were so leaky that they didn't even hold.  Replaced all the vacuum lines in the advance system and it worked alot better.

just my