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Interesting thread revive.
It should be true. If I understand how carburetors work, the cam profile matters much less for combustion efficiency than with MPFI, since the fuel has so much time to vaporize.
High static compression ratio plus late intake valve closure is exactly what the Prius and many other engines today do. The reason this is a great idea for modding an engine if you can tolerate the loss of low end torque is because at high engine speeds you gain the volumetric efficiency back and actually make more power.
The strange thing is that with a carbureted engine, with cams that big you would expect a lot of fuel to be blown out the exhaust and wasted. My guess is that they kept the exhaust cam reasonable and not open early to prevent that.
The reason you have never heard of this becoming used widely is precisely the fact that you are losing a crapload of low end power. If you're bleeding off half the charge, you're basically getting the fuel economy of an engine half the size, and also have the torque of an engine half the size. VVT is nice because you can bleed off the charge at low throttle, then adjust the cam back to get your torque back when you need it.
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