273 Carb Size

[1] Nobody mentioned VE, unless I missed it. These charts assume 100% VE at the designated max rpm of the engine & production engines would be lucky to get to 80%. That means the carb size needs to be 80% of the chart size. So as an example the engine will only use 480 cfm of a 600 cfm carb at peak rpm.
[2] Another important principle has been lost. Somebody said use a 750 vac sec Holley & the engine will 'only use the airflow it needs'. Yep, true.....But 750 Hs have 1 11/16" pri & sec bores. A small engine like this could use a 500/625 AFB or AVS which have MUCH smaller primaries, 1 7/16" & have enough airflow. The smaller primaries will give better throttle response with no downside at all, & on a small-ish engine that needs to be considered...