Doggy Performance

[1969f1004x4SB]

Hello all, I got a 1969 F100 with a 360 that's been stalling every time I touch the gas pedal. The ignition system is completely new and electronic, and the timing has to be set way past TDC just to run somewhat decent. (I verified the harmonic balancer is accurate, unless it slips while rotating and returns to the correct position when engine is stopped.)
Just threw in a new accelerator pump, but the old one I removed looked to be in good condition. I've noticed that the RPM will slowly drop when the gas is held at the same position. It probably relates to the sluggish acceleration, but it feels like the engine has lost half of its power since I got it about 8 years ago.

Looking for any suggestion since I'm out of ideas right now.

[1970FordTK]

Power valve might be going out.

[cep62]

Try and diagnose if your timing chain slipped.
With the cap off see if the rotor is pointing close to #1 at tdc.
turn the engine back and forth with a wrench and watch the rotor it shouldn't have too much delay.

[Jbarnes79]

You could be a tooth off on your distributor.

Lag or stall when pressing the gas could be too much gap between the accelerator pump and lever.

[Raiver]

Start with the timing chain suggestion and update us.

[1969f1004x4SB]

Thank you for all the suggestions. Timing was correct for the chain. It was determined that the accelerator pump was the source of the issue. Sent her into the red after installing the new pump and ran perfectly after that. Starting to wonder if something was stuck, but will never know.

Thank you all!

[Raiver]

Good to hear you figured it out!