Joey - Looks cool! FYI you generally will want to aim your fuel injectors to hit the back of the valve. Otherwise you'll be wetting the port wall. That could cause driveability problems as fuel sloshes off unevenly.
Well, that's kind of what i was going for...... the injector actually points at the valve and long turn or top of the intake port. The conventional orientation has it pointing mostly at the floor of the port ( take a look at the Edelbrock FI intake ). Not sure its better or worse, but there are other manifolds out there with an identical injector layout and they tout that as being a better design..... Who knows till you try right?
I just liked the idea of hiding the rails and injectors under the manifold and mostly out of sight.
The trick will ultimately be either casting that runner in aluminum, or being able to print it directly with a material that is up to the task.
Casting it isn't out of the realm of a home jobber, its small and there are several methods a guy could try. Printing it would be ideal, but current hobbyist level printers may not be up to the task when it comes to using materials that will last under a hood. Though, there are some really cool fiber reinforced filaments out there....
BTW, that throttle body costs $33.00 on Ebay, shipped. So you can get 8 60mm TBs for $264, delivered. That's about 1/3 to 1/4 the price of most name brand 4150 based "air valves". Still have to sort out the idle control, but that goes for any ITB.
I have another iteration of this idea in the works, actually a bit more excited about it. It is a similar design, but pairs the runners up side to side, and uses a Coyote (5.0l) ford twin 55 or 60mm TB. You can buy these TB's new from ford for ~$120 and they are DBW, I picked up a brand new take off unit on Ebay for $85. the DBW presents a bit of a control problem, but also gets rid of the linkage headache. I have the TB on the way, and just ordered a 3D printed version of the runners.
Ill see if i can post some renderings to show the general idea...