White header pipes?

[CHaingKaiShek]

I'm really not too sure what the problem is here, but maybe someone can lend me some insight as to what the issue may be. On my truck, I have a fairly cheap set of flow-tech headers (Hey, they work.) However something odd is happening to them.

A few miles after the install, of course all the paint had baked off, no big deal. I Didn't really expect the headers to change colors much more beyond maybe rust brown but infact, they have turned white.

A white power like substance is forming on the outside of them all. It can be cleaned off via the use of water and a rag but it returns with a vengence after running for a short while.

What is causing this? I thought maybe a lean condition, but the spark plugs aren't showing signs of being lean at all.

Thanks in advance.

Jeff