Civic EG

Okay i just got an intake mani but its pretty dirty. It has oil, and alot of build up on the outside. What can i do to clean it?

Sandblast it

Sand Blasting works, I have used Carb Cleaner and Rags/wirebrushes before to clean up blocks/transmissions.

oven cleaner

soak it in simple green and throw it in the dishwasher

Use someone else's dishwasher and don't wash any dishes with it

brake cleaner for the inside, it murders it.
simple green or Purple Power it, then use fine steel wool to get the last bit, then prime it, i used self etching primer and it does good, then throw on some high temp aluminum paint