Yes these are milled 30 thou. Compression is determined by altitude. i ran these on pump gas at approx 1500 ft with no problems. Can't remember the compression at that level but ran great.
I have a polished milled 30 thousenths head for a little more compression. Can still run pump gas with it. For $50 plus shipping. It has been sitting iin my garage and Just needs a little mothers polish.
Let me know.