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Thanks for the insight, especially Andyman and MechEngVT.
I would be hesitant to go more than a few thou on the lash over spec, as you've said. A cam profile slowly lifts the valve off its seat, and rapidly opens and closes it before gently setting it back down. Throwing a 0.030" clearance in there would probably prevent the "gentle" beginning and end from taking place, thus increasing the stress on all parts in the process. I really do think more economy is possible through drastically reduced duration & lift, and this would be the easiest way. But I can buy a lot of gas for the price a new valve-train.
And I never thought of manifold vacuum helping with atomization (2/3 throttle vs. WOT). Interesting.
Ideally, I'd like my 1.7 to make peak horsepower at 4000 rpm and peak torque at 2500, but that's asking a lot, as it's around 5800/4000 as is. torque would remain the same, horsepower would obviously be much lower, like 75 or so. I need someone who has the machine to grind camshafts to my spec. Yikes...that would be a cool machine to have.
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