Reply to "Is it possible this thing works?"

We used one of those with two springvalves ( or how do you call them ? ) that came off a vorklift truck that was running on LPG. The spring valve is just a big valve opening on the engine vacuum and thus sucking a lot of air and LPG in the manifold. Because LPG is a liquit gas, it cooled the air going in the manifold producing a lot of power.
This way we made a dragracer on LPG. It was succesfull however LPG is burning on a higher themperature, so engine cooling became a problem.

The other way you can use them, is placing your webers in a horizontal way. this will keep the set up much lower, like this Bizarinni. The 90 degree adaptors between holley and weber patern are on the market.

Arno