who has used it?
Did you spray it or did you just brush it on?

you can bush por15 or spray. spaying would look nicer, por15 is used for rust treatment don't think i've seen it used on a engine block.

http://www.por15.com/ENGINE-ENAMEL/productinfo/EEPA/

not not Por15 but por15 engine enamel

i haven't used that engine enamel por15, but i have seen and used black velvet (made by por15 for high temp) and it's good stuff.

it's a good brand, i would trust it.