Lurching in 1st gear, esp when cold

[Pgh5spd]

Stock '93 L, fires up just fine, and moves in reverse just fine, but then taking off it lurches/surges. After that it runs out fine, just like always, and responds when I step down on it (and so I don't think the fuel filter or injectors are at issue), After it warms up the problem is greatly diminished. The brakes are not sticking, either. Thoughts?

[FestYboy]

timing curve or possibly clog in the vac line to the fuel pressure regulator.

i'd check timing first, then go from there.