Sorry, missed your question.

The Holley 4150 list 1850 is usually the most encountered 600 cfm unit. (I think it's actually 585 cfm.) From my old Holley catalog, they list 1.25 primary venturis and 1.3125 (1 5/16) secondaries, along with 1.5625 throttle bores.

They list a 2300 2v, list 0-4782 rated at 355 cfm (remember that 2v carbs are rated at a 3.0" pressure drop, but 4vs are rated at 1.5". Convert using square root of 2, about 1.414, so that a 500 cfm 2v = a 390 cfm 4v). Anyhow, this 355 cfm 2v is listed as having 1.1875 (1 3/16) venturis and 1.5 throttle bores.

If memory serves me right, the last Holley-Chandler Groves type carbs that came on Fords in the mid 50s, like the EGC types, had venturis around 1.0625 or thereabouts.

Regarding alcohol, I cannot recall which is which, but there are two kinds, methanol and ethanol. One kind requires abotu a 9:1 air to fuel mix, and the other requires around 6.5:1. Both are hygroscopic, or have a great affinity for water, which will degrade their use as a fuel. Both attack zinc parts and rubber parts, such as one finds in carbs and fuel pumps. Both will decrease the miles per gallon considerably, so you will need a bigger fuel tank to maintain the same driving range. Then, there is obtaining a ready source for whichever one you use. Lucas (Lobo) should be able to speak to alcohol use much better than I can, because Brazil uses a considerable amount of it as automotive fuel. Beyond this, I'd have to do a little reading, and because I'm a bit pressed for time at the moment, I can't do this. But some web searches might fish out some info.

Propane, it seems to me, is a more practical alternative fuel. In our country, regulation has pretty much quashed the building of any new refineries or pipelines. So, as people insist on the return to 12 mpg monsters to commute to work, the extra capacity has to come from somewhere. Off shore refining makes gasoline much more expensive, and pipelines operating at capacity mean that fuel must be shipped by tank cars on trains.

The cost of crude is only going to go up as 3rd world countries increasingly use automobiles. China is booming in the population's use of cars, and now they will be competing for oil on the global market with us. They can use all of the billions of dollars a month we send to them (Walmart is 1% of the Chinese economy by itself!). There is the added benefit of this formula that, with every gallon of gas we buy, another AK 47 is bought by Bin Laden with money funneled to him from rich Saudi ruling family members.

All this is to say that your investigation of alternative fuels is probably justified, as gasoline is only going to keep increasing in price, making the inconveniences of alternative fuels more acceptable, and perhaps more necessary.

This is all just my opinion, of course, but it does seem to be borne out by what I do know and everyday's news.