Re: cheap.........HEADER PAINT!!!
When new headers are painted by the manufacturer they use regular paint. Header or high temp paint wil rub off at the touch until it is heated. What happened is normal. You just burned off cheap paint. If you want your header to have a decent paint job scrape all the existing paint off, wipe it down with acetone or laquer thinner, paint it with high temp paint. Don't touch it. Start it up and let it get hot. You're done. It will smoke a little and smell bad for a bit.