New here, I just bought a 2004 Denali XL with a Joe Gibbs Radix supercharger, and it has some fuel issues, the PO said it had gotten hard to start so he replaced the walbro 255 with a new one, but the problem is still there, it looses its residual pressure in the rails after sitting for a few minutes. I dropped the tank today and it has a walbro GSS340 in it, which has the big center inlet pick up, but It needs the side pick up (342)?? not sure if this is the issue. Also with a full tank the thing runs great, at 1/4 it acts like its running out of fuel, and actually stalled a few times. Any help would be great!

Here is a pic of the basket that it has, anyone know if the check ball under the grey cover keeps the pressure in the line or is it something in the pump??





and here is what the beast looks like: