First thing you need to do with the runners before it gets welded is round the inlets inside the runner so its more like a velocity stack instead of just a squared off hole leading to the head.
I dont buy into this volume argument for the intake. Certainly bigger is better to an extent but dont forget here the intake manifold is pressurized. Which means every square inch of the intake from the compressor to the cylinder head is pressurized equally. So in theory every bit of air intake that is available will be shoved into that cylinders intake valve for hte brief moment it opens. I do agree that the setup thats in the pictures with the square tubing is too small to make top end power. But I still believe it would be a 12-15whp increase at the least over a ZE manifold just because the single chamber design.
I plan to make a nice welded intake too but I dont like how tight te injectors fit in there. The best way to do this would be remove the stock injector rails entirely and mount the injectors on the outsite of the runners and point them more towards the intake valves so its a straight shot instead of how inefficient the stock setup is. Just some constructive criticism for you to mull over going forward. Good luck with the project, looks great so far!
