I skipped the 1st poll and jumped to the 2nd.
Buy stainless steel pistons in you can find 'em, or throw those plastic puppies back in and run 'em!

Supprised at how nice the bores look. Don't no about the swelling thing, but the problem I had with phenolics was they would stick in the bores -you could see little chatter marks on the sides of the pistons. Had lots of problems with them on squad car applications. The fix was to go to steel pistons.