I had a tight fit in my 440/493. It was an odd situation. I had a '509 cam in there and it seemed to spin freely. I was changing cams to a Lunati and it would not spin! I had a stock 440 cam that I cut grooves in, then I packed the grooves with bearing grease to trap the shavings. It was not a 5 minute fix...I had the cam in and out a few times to clean the grooves and reapply grease. I did it until the cam spun freely with the cam sprocket on. My machinist (Not a dedicated Mopar guy but knowledgeable about them) said this is rather common in big blocks and is actually mentioned in some Direct Connection catalogs!