What would it take to make 1.44 lbs-ft per cid ?

273 said

If you look at what port size cc is needed for a given cfm to make a velocity of 260 fps are roughly.

225 cfms = 170 cc, 250 cfms = 190 cc, 275 cfms = 205 cc, 300 cfms = 225 cc, 325 cfms = 245 cc.

If 260 fps is the ideal for best balance of torque and hp. Supposedly above 320 fps hurts hp below 240 fps hurts torque. If correct it seems like we generally don't have enough port for a given amount of cfm.

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When you get the port too big, lower RPM torque suffers. Look at the Ford Boss 302 and Clevelland 4V heads. Huge ports and low RPMtorque suffered. They came alive at 4000RPM. CHI developed Clevelland/Boss heads they call 3V that are 4 barrel quench combustion chambers and 2 barrel ports. Realise Ford Australia used the Clevelland engine for a while after Ford North America dropped it. They also built piles of 302 Cleveland engines.
Airflow in a port stalls at some point, limiting velocity and flow. Working to get high flow velocity builds pressure in the bowl and aids cylinder filling as the piston rises before the intake closes on the "compression" stroke. This greatly aids cylinder filling and density.