Hesitation with a cold motor

7upstang91

10 Year Member
May 30, 2008
936
124
74
Florida
Just transplanted the new motor in. Starts perfect, idles great...but if not driven dies. When driven hesitates the first half a mile of driving, in the lower RPM range and in first and second gear. Once the car gets past that first hesitation it takes off, at a good rate. Once the car is warm, no problems at all. This is my notch, but now has a cam in it. Any thoughts?