This is a cheap carb conversion I did on the stock 261 in our 51 Chevy truck.The carb is a Holley 2300 off a 68 IHC scout with the 266 V-8.I removed the top of the stock intake where the old one barrel to match the Holley,made an adapter from inch thick phenolic material, bored 2 holes to match the new carb throttles, tapped and drilled a few holes to secure the adapter to the intake manifold, fabricated a linkage.Nothing fancy,did it all with common tools.The Holley flows about 220 cfm when rated like a 4bbl(310 cfm rated as a 2bbl)It has far better response than the single barrel with slightly better fuel mileage.
Fleetside, who told you a Holley - Weber can flow 330 CFM??Rated like a 4bbl, they flow 200 cfm according to Holley specifications.
Holley on a 261
