Interesting....I am far from an expert and installed dual carbs on a 235 that ran quite nicely....A pair of the smaller Rochester B's (216) on a water heated Edelbrock intake...Stock main jets, I think they were #52's...I carefully removed the high speed "jets" (power valve) from the holder,measured them with a drill , soldiered then shut and redrilled the hole .003 smaller...I re curved the distributor mechanical advance by brazing the advance slots to about 2/3 it's travel and stretching one spring .....Set the timing to 36 degrees at full advance around 3000 rpm, it was about 10 degrees at idle...Modified the vacuum advance by putting a piece of wire on the slotted arm to limit the advance a bit....I used 89 octane fuel....The engine ran better than stock and got what seemed like slightly better fuel mileage... This was all there was to it....And yes the Rochester B's did seem a little fuel like most do...
If you can search back on this site to the early days of this site you'll see quite a few guys were running dual carbs and reporting the same success without using dynos or any sophisticated tuning. Joe H might remember some of the names... Grant and Cosmo ???..It's no secret the single carb in the center of the log intake has terrible fuel distribution and two carbs is an improvement...
