O.S. MAx .40 H Question

I have a couple of these engines that I purchased on the "bay". Although they are set up with a venturi and OS NV assy, neither has the original factory set up. Well according to the O.S. MAx history page picture (see below).

The point is that the current large O.S. Max NV bottoms out on the nut that secures it before it closes off completely. The casting is thicker than the casting on the S series at the venturi and the nut is closer to the needle and the threaded portion of the needle hits which causes the problem.

My recollection is that the current large O S NV assy. is the same as the one produced in the 60s'. In fact I have compared a recently purchased NV with one I had in package from about 1968. They are the same.

Was there a special NV assy used just for the 40H series engines?

LAST EDITED ON Nov-18-04 AT 07:43 PM (CST)
 
Divot,
Ask me about this Saturday, I have something to show you. You may be able to use a r/c nva.

Actually, they did use a special needle valve for these that was .135 diameter but longer than the FP version still available. I drill these out for a .155 needle and use a medium ST needle in its place. The PA assemblies work well here, also. (Oh, and make sure you resize the venturi if you use the larger needle.)