I put the a whiplash cam in a 440 today and it was tight. The factory cam that came out of the motor was tight coming out I had to use a dent puller/ slide hammer to get it started but once it was out about 1/2 inch it came right out. When I put the whiplash cam in it went right in except for the last 1/2 inch after I put the timing chain on the motor turned freely (with no heads). The bearings looked good and none of them moved. What would cause this ? Should I be worried?

There is probably a lip on one or more of the bearings where the cam did not ride, and some babbitt may have piled up there to cause you a little grief. If it turns free with cam gear on it riding against block, you may be good.

My machinist commented that Chrysler cams are often tight. Back in the day the factory did not do such a great job of aligning the bores for the cam bearings.
Align honing is. The only way to make it right. He did say as long as you can turn it by hand you should be ok.

I could turn it with a crank socket after the timing chain was on but turning it by hand at the cam was hard. But it did go in about the same as the original came out and turns about the same as the original did.