Engine starts to stall in begining phase of plane out.

[Beech2000]

5.7 litre
Edlebrock 750 marine carb
MSD Ignition
23 pitch quicksilver 3 bladed stainless
Alpha One Gen II 1.67

This problem just started.

From idle and during acceleration all is normal up until point that I stop increasing the throttle position during plane out. The engine accelerates perfect meaning the shot from accelerator pump is working. The engine sound almost as if its going to stall that is until I throttle back and posistion throttle to WOT and engine runs normal from this point on.

I suspected water in fuel but disassemble of carb and water separator filter revealed no water but did find several small particals of dirt. No big deal though. I then removed lid from top of edelbrock carb and all was clean as a whistle.

Went ahead and cleaned anyway but now puzzled.

The one spark plug I pulled looked good. slight tan colored with no detonation particals noted.

I still think It has something to do with the last load of fuel as this is the only variable for at least a month.

I would love to hear feedback for explanation or possibility's that I have overlooked.

Thanks

Kevin

[gonzo]

It may be the primary jets or passages clogged.

[Beech2000]

Wish it was Gonzo.

Pulled Primary and Secondary metering rods and all 4 jets out. All clean.

Wonder if fuel bowl level is set to low. I checked the drop and measured about 7/16"

But why does it recover so nicely.

Ignition? Vapor lock?

Thoughts?