Another Pass

4° advance. Turn it 7200 on 1-2 shift 6800 2-3 shift. Trap rpm in the quarter around 7200. Heads have been fairly well ported, but not my best. Flow 265/185 on a SF1020 which would be close to 280 on a SF600. I have a junk head that I did some experimenting on that hit 280 on the SF1020 which would be like mid 290s on an SF600. If I get ambitious I'll work over a set for next year. I plan on swapping the cam this week for a custom ground Bullet.
Old cam specs 252°/252° @ .050 164° @ .200 108 LSA +4 .528
New cam specs 257°/260° @ .050 172°/173° @.200 108 LSA +4 .563


Why such a difference between the two flowbenchs. Dont they calibrate them.