What type of engine is this?

[BB500]

I bought a used 1991 928 engine. It looks beautiful and original. The valve covers and intake are silver, but the Porsche lettering and valve cover bolt washers are red. It looks factory, does this color combo sound familiar? He didn't know what type of 928 it was from. Less than 100k miles.
Sorry I don't have any pics of it, it is in the garage at our new place and we haven't moved in permanently yet, so I don't have a set of keys yet.
Is it possible to look it up by the numbers?