My ideal manifold would be a spreadbore to accomodate the Q-Jet. However Offenhauser stopped making spread bore dual planes. I used a square bore manifold and bored the secondaries and primaries in the manifold to match a spreadbore carb, and made my own adapter. No one makes exactly what I needed so I made it my self... Here's sopme pics.


Sorry for the image size. I used a ball end mill to get the primaries to blend and a regular boring head for the secondaries. I used a piece of 1/2 alum. plate for the adapter. The manifold had plenty of material and bored fairly easily. I used a two-flute end mill to cut the perimeter of the adapter. One of these days I'll get a grinder to it and make it look pretty...