Fear of spring loads?

Go back and read through the whole camshaft/valvetrain sections of the MP engine books.
Read what is said about the spring loads....... then look at the recommended spring part numbers...... and the specs for those springs.
Especially the springs for the bigger flat tappet cams.

Then consider how everyone talks about how old school they are, and that newer, faster rate cams would make more power.

Well, generally........ the faster rate profiles need more load to maintain control of the valvetrain.

Look again at the recommended springs and loads for those old school lobes...... and let it sink in that the newer designs should use more load than that to achieve similar RPM’s before the onset of instability or float.

It doesn’t point towards loads in the 130/330 range being able to get it done.