Stumbling after Walbro in-tank pump install

[driftinblzr]

Hopefully someone here can shed some light on a problem I'm having.

I recently replaced my dead stock pump, in my '02 Blazer, with a Walbro 255lph in-tank pump designed for a 3rd Gen F-body (GCA758-2). The Blazer uses a small siphon tube and plunger looking assembly on the stock pump so I reused it on the Walbro as the pump themselves looked the same externally.

Now the problem I'm having is when I'm at 1/4 or less, during moderate cornering or heavy acceleration, the Blazer seems as if it's running out of fuel.

What I'd like to know is could it be the Blazer's siphon system is causing a bottle neck when it relies on it or could the fuel pump be pushed too far into the plastic bucket the tank uses?

I know I shouldn't run less than 1/4 tank but in the event that I do I don't think I should have to be gentle on it until I get to the gas station.

Thanks for any help or insight.

Later, Doug

PS. I took this pic from another forum. The red ovals refer to the siphon tube/system.