Mopar Performance Purple Mechanical Camshaft - P4120653AE Cam Card

I can tell you from my experience with MP cams...all the durations @.050 are incorrect. They are calculated number
I have used many MP590 cams for small blocks....MP shows 265 @ .050 my degree wheel shows 271 duration @.050

Same with the MP557 cam....MP 252 duration....my degree wheel keeps showing 258 @ .050
As said put in an engine and run a degree wheel on it......only way...