If you insist on using a dynamic cr calc to tell you what compression ratio can be used with a cam, you had best convert the Crane @.004" spec to a good estimate of the spec @.006" which is what the calc needs for an input.
A good estimate of the duration @ .006" will be 275° in and 283° ex.
Now redo the dynamic calc.
garbage in = garbage out
If you need this cam on a small base circle cam core for stroker rod clearance or want it on a different LSA like 108° call Crane Cams. They can custom grind.
If you need clarification on the difference between .004 and .006 advertized seat durations, and what that means
and what this cam actually measures at .006 ask Crane cams tech.
Last edited by F-BIRD'88; 02-06-2011 at 12:18 AM.