Sometimes my engine (DOHC) makes a clacking noise that you would think was a rod

What is your question?

When it's been drove for awhile it clacks a little more than usual. sometimes it don't clack at all. Fresh oil turns back rather quickly. Neon website said it might be "piston slap". Never heard of that before. Doesn't show up on a code reader, and another Neon owner said he's had three Neons, and two clacked just like mine. It still has plenty of power and goes like hell, but make a ..... clack noise. any ideas?