[Union Forge]

I would just have nice sturdy flanges cut from aluminum, and weld strips of sheet at a width equal to your desired height and then use them to fabricate the walls and top or lid of your spacer, rather than try to machine it from a solid piece of aluminum. As mentioned above, such a piece would be outrageously expensive.

edit :: you could actually then make the "lid" section any shape or dimension desired. The flanges would be relatively cheap, and you could just have 5 or 10 cut. if it only took 3 or 4 to figure out your design, you'd have a few left that you could sell. of course that is assuming that you have the means to weld aluminum, and that there would be a market for them. But it seems like it could be a fairly sought after item if the intake isn't one of a kind. Sorry just skimmed over the thread but wanted to try and give some helpful insight.

 

[GasInMyVeins]

There are a bunch of places online that do 3D printing. Maybe that would be an option?

 

[daffe]

was the spacer realized?What was it made for ? gain or not ?

 

[zippy_109]

I don't think it ever was. I had a friend w/ a machine shop who owed me some $$. I tried to get the work from him, but he ended up just sending me a check for the debt. Since then Powerdubs sold his R w/ the aluminum manifold. I have a spare stock plastic manifold I've considered toying with in this way. I'm not sure how well it would hold up to mods. Even NA you can see the manifold expand and contract under on/off throttle.