First things first: You need a walbro 255 minimum to pump fuel to those injectors. Second, those injectors aren't exactly small, whether you're running a return fuel line or returnless. Either way, are these injectors brand new or used? Sounds like they need to be flow tested, because the fuel rail wouldn't select 1 and 3 to not get fuel. If it was a returnless setup with a fuel rail, cylinder 4 might be getting the least amount of fuel but that doesn't happen either unless it's a poorly designed fuel rail. I'm running the same rail, 1000cc FIC injectors, returnless. Get back to me on these things, we'll figure it out.