I have seen 30 CFM variance between ones I have
tested. That does not include some castings that came
from the factory so darn bad that I rejected them upon visual
inspection. I have seen exhaust port 1/3 closed from core shift.
They used the castings over often 10 times back then before discrding
Look at the # after the 894 IE: - 1 to 9. Every time they used the
casting they raised the # on diget. Generally the core shift is seldom
anything but detrimental. The lower the number of times the casting
was used the better the port configuration!
