What kind of carb and choke? exh. heated choke tube or electric choke or manual choke?
A pic with the air cleaner off would help a lot. Your choke may not be opening fully when warm.
Could also be that your timing is off, do you have a timing light?
'67 Coupe 289 stroked to 333, AOD, 9" w/3.50:1, PDB, Candyapple red w/red deluxe int., PS, ext. decor group, light group, foxbody seats.
'09 Black Warriors In Pink with glass roof - the wifes Mustang.
"If it ain't broke, I haven't fixed it yet" -Jon