Dont bother calling them the plastic there reffering to is the powder its self if you look at there advantages page it lists the coatable materials which are all metel besides the glass. I have been powder coating for about 2 years and it is not possible for powders to cure at low temputres yet although our ppg sales rep says its a work inprogress so maybe in a few years it will be possible.
false advertising for the first company you suggested...but i understand how it is termed now.....new info...i got into contact with ford techs, the temp. rating on the cover is 400*, but that is right on and probly a little to close to risk ruining the covers.
I'm one of the few that have painted their VCs the thread I started was lost when the system crashed. Below is a thread started after the crash with photo's. And although it may not technically be called powder coating, Modular Powerhouse says they powdercoat valve covers contact them and see if they'll do a manifold.