Stinger has no provision for manifold heat? Or, it's not working.
The manifold heat (small pipe under manifold) is essential for acceleration. The heat right under the carb vaporizes the glob of fuel when you put your foot in it. Without the heat, the glob just sits there and the engine stumbles.
In summer, you *might* get away without manifold heat, but it still won't perform as nicely.
Assume you've already checked the accel pump jet and the vac advance/retard is working.
Speedy Jim