Hello hartside,
Yes you can paint your motor with just about any type of paint, some have better hold out qualities then others.
I have found that the acrylic enamels, acrylic uerathanes work rather well.

If you want pearl over a certain color on your block it can be done using a compatiable clear with the pearl added in the clear.

But the more Mill's ( paint thickness) you have the more chances of it flacking off in time.
Just make sure you throughly clean the outside block surface with soap & water , then a good wax & grease remover , then 1 coat of epoxy sealer, then spray your color.

SprayTech