I'm not sure, but since the
Holley 847 has a 1-3/16" venturi and a 1-7/16" TB, given what I have learned here so far, I'd say that they are too big for for a dual setup on a street 235.
Jon recommends the 215 carbs for a mild 235 on his website, at least if you are sticking to
Rochester multiple B's .
One thing I have been noticing is that if you look at the horsepower of the intended application (for the Holley 847-F 90 BHP--the 847-FS is bigger) then multiply by the number of carbs you intend to use, you can get a good idea of whether they are the right size or not. So, if you want to use two of these Holleys, you should be planning to build a 180 BHP engine.
The 215 carbs are meant to support 60 BHP, so two would suppot 120 BHP and this is much closer to what I think a mild 235 will produce.
I know this is not absolute, but I think it gets us newbies in the right ballpark. Just how I've been thinking.
