The Weber 32/36 (DGV) carburetor has a larger bolt pattern than the stock Hitachi on a Datsun A-series engine. You can modify the stock manifold, or use an adapter plate.
You can make a DGV-compatible intake:
But most of us use an adapter plate:
Adapters for many models are available for sale, but I made my own adapter for the Nissan A12 engine out of a block of aluminum:
Make Your Own Plate
- Dimensions: 1 x 2.75 x 5 inches (minimum would be approximately 10 x 6.7 x 11.4 mm)
- Using a Nissan gasket as a template on one side, and the Weber gasket on the other, mark the holes.
- Drill two bores ~30mm and 27mm to match the intake manifold. You might have a machine shop do this; I had access to a lathe with a large bit chuck into it.
- Drill and Countersink holes for stock Nissan pattern using a drill press to get them straight.
- Thread holes for Weber pattern
- Use a round rasp file to smooth out the transition from the small Nissan bore holes to the larger Weber holes you drew from the template