Dad, the 261 in my 37 with the Fentons, cam and more carb was something I built that way from the start.But compared to the "stock" 261 in my 51 truck, the 37 is quite a bit more lively,and revs easily to over 4500 rpm, something the stock 261 won't do even with the 2 bbl carb.Of course the 37 weighs 400 lbs less, but both have the same gear ratios.
I would say the 2300 Holley 2bbl added maybe 10 hp? It idles better too starts instantly hot or cold.
Boo, the 5200 is an excellent carb, but it's my opinion it's a bit too small for other than a stock engine.Holley rates all 5200 at 280 cfm,but that's a 2 bbl rating. To compare a 2 bbl to a 4 bbl,you must use a factor of 1.4 more or less.So the 5200 becomes 200 cfm it you look at it like a 4bbl.Anyhoo,the best way to know is to try it out on that hotter engine,if it works for you ,good enough.I'm thinking a Rochester flows 70 percent of the 5200. On some engines,the small primary throttle of the 5200 kills a little power at part throttle.I know a guy who modified the linkage so both throats open together, he claimed it was a good improvement with no loss in economy.
