You have that B18 generator? Yes, I'm that fool. ;-)
About the tune, where is your port? This is one of the alloy intakes that has a plug screwed into the front (radiator end) face of the balancing tube. IIRC, not all of them have it. I put that valve in there with the idea that I might be able to use manifold vacuum to activate some sort of governor arrangement, but that didn't work out. The tuning trick was a serendipitous by-product of a failed experiment.

The generator is still a work in progress(?). The two cylinder B18 runs beautifully now with the modified HS-6s (re-drilled jets and GT needles), but I'm still having problems with the governor being too slow in reacting and the bearings in the Chinese generator head are noisy and need to be replaced.

Despite the above, if that A cam isn't doing you any good, I would still like to buy it. One of these days I might run into an A-type manifold and maybe even a Zenith carb. I think a single carburetor set-up would be easier to control with a governor than the dual SUs. So, if you are still willing to part with that cam, please mail me at rsilvius at earthlink dot net, and we'll work something out.

Bob S.

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"62 PV544 (B20, M41), "71 142E, "93 240 Classic Wagon.