79 2000 cuts out or sputters on load in 5th geer

[barnesjtsl]

Took off and threw away the ADHA and manifold. Installed a 32 adf and single plane manifold.

Did this carb upgrade last summer in June and drove through October with no issues. Then garaged it for the winter.

I just took it out a few days ago and it was running fine until I got into 5th gear around 55 mph and laid on the accelerator and it started sputtering/cutting out. I found that the timing was off a bit. I reset the timing and took it out again and the same thing.

I have a gas filter on the line before the fuel pump and another just before the carburetor.

The fuel pump is a little old, so I'm thinking of getting another one and new filters and trying that.

Anyone experience this before?