[SCOTI]

I've seen them painted w/regular PPG primer surfacer & urethane top coat. The key is the prep. Also, there will be areas that will suffer the consequences of extreme heat & discolor more than the rest of the motor w/time. For my stuff, I just taped everything off, Simple Green'd the crap out of it, scrubbed it w/a stiff brush, then rinsed it w/another spray bottle w/water. Let it dry overnight, then hit it w/some reducer/laquer thinner & a lint free cloth. Get every nook & cranny. Let it dry then do it again. Just prior to painting, wipe it down w/automotive paint degreaser (alcohol works well too) & paint. Do the hard to get areas 1st w/a light 'tack' coat & then spray the whole motor w/nice even strokes. Keep it as thin as possible because too much paint by the exhaust ports will chip in the blink of an eye. I just used VHT engine paint (cast iron grey). My buddy used regular Krylon on his 455/Olds & only had fading by the very tip of the exhaust ports.