What color should I paint my engine?

I have a 68 Formula S and struggled a bit with that same thing when I did my 416 stroker. I went with Mopar/Hemi orange and am glad I did. I have an off brand motor I built that I painted black and covered the frost plugs so they were still gold in color. It looks OK but kindof looks like a generic crate motor after some time. The Mopar orange still looks very good after a year.

My 2 cents I would go red for a restoration or orange for a fun car.