After break in

I agree, I've heard the same, but here's the way I'm thinking: I had a 22 minute break in, some people go 30 minutes, so another 10 minutes of running on the stand shouldn't impact ring seating, it'd just be like the extended break in some do.

 

The best break in is driving it

 

What compression did you end up with the Rover heads on the 300? What piston?

 

Static ended up at 10.02:1, I have the 26cc dished silvolite pistons. I kept the stock valve setup, if and when I rebuild this guy again for boost in the future, or get another 300 for it, I'll take your advice on larger valves and how to get a little more lift out of them.

 

I hope that'll happen sooner than later