Using the old 4.1 cfm per horse per cylinder, another 30cfm (Ryan's stage 2 porting) should give the motor another 55 or so HP and another 500 or so of Rev cieling.

What concerned me was being able to run the 1/4 mile without the motor gasping for air past 1000 feet or so, I figured the cam I'm running with unported heads would peak around 5600 and the motor would start laying down around 6000-6100. The Extra cfm should get me to ~6500-6600 and let me pull the 4.56/29.5" gears/tires up a bit higher.

What kind of RPM are you solid flat tappet bracket race guys shifting at? I've always found when a stroker is built right and has the right cam you can short shift it ran nearly the same ET's, ain't torque great?