Cleaning an aluminum engines (LS-1) exterior ?

[GriffithMetal]

Originally Posted by GregWeld

I'd have to look into it to see what they painted it with - if anything special. I'll get back to ya.

I would guess it was a basecoat/clearcoat paint job?
The best way to clean oxidized aluminum is with mild acids. It's not fun or easy but works the best. Mag cleaner or specifically designed aluminum brightener like PPG DX533 followed by a conditioner like DX501 work the best to give it that as cast finish but it won't last forever. Paint would be best for low maintenance. Be careful using acids!