89 thunderbird supercharged 3.8l, long cranking time when engine cold

bought car 4 years ago, 88,000 miles, now has 125,000 mi.has always had along crank time before firing. seems to be worse when teperature is low. has new starter, battery and fuel pump and filter.cranks fast and seems to run great, 28 mpg highway.would really like it to fire up faster, especially in case i want to sell it someday.thanks for any help