Hemi Swapping a perfectly good 70 Duster

For those following along here, I went to autocross this past weekend. This was the first time since I had the power steering problems last time out. I'm happy to report the modifications (corrections) I made worked. It was also the first time successfully around the cones with the hemi. Very different power band than the 408. The car feels much more balanced now. But I changed a few other things so I doubt the engine has anything to do with that. Data log says the holley cast pan is doing a good job controlling oil in the turns too. However, it may be time for the corvette filter/regulator to go. It shows a 25psi fluctuation over the course of a 42 second run. Likely not a problem for a street cruiser, but it may be best to have a nice constant pressure with the throttle transients required for autocross.