I agree with it too....I told you at the GATHERING you needed to go bigger *It suggested a few for my application....I like this one: https://www.holley.com/applications/CarburetorSelector/0-80514-1
That formula is simply a tool to get you close to the right size carb. It by no means tells you the optimum size carb your engine will like best.
Pretty close. I started with a 600 CFM Holley, ran a 750 VS for a while, went to a 4100 600CFM and she loves it. Never looking back.
...same here...my 302 had a 600 CFM Holley...when i built my...roller Motor...i went with a 650 DP...it was "too" lean on the dyno. i got a 750 CFM and it was still "too" lean. i set up another dyno run at a diff. place and asked him what carb. he wanted to start with..."600 CFM Holley"... we did 2 pulls and he pulled it off and started playing with the air bleeds...too rich. i had to get an adj. metering block so we could lean it out... ...the 650/750 were so big they couldn't pull any fuel... my new moter he built...he suggested the 600 i have on it now and we will fatten it up... ...as we know...all engines are diff.... ... ...
Yup! bigger carbs will run leaner than small carbs but the car may have better mixture control with a slightly bigger carb where your engine is making its power. You just have to tune it more than you would a smaller carb. No easy answers but good guidelines.
Increasing jet size isn't a way to overcome an undercarbed condition. That only increased the fuel to air ratio, making it run richer.
