have brains enough > have enough brain.

Technically, yes. This is a somewhat more colloquial and emphatic way to say it.

@CK: Right, I didn't notice the lack of an "s" there.

@duran: The most correct/normal way would be "have enough brains" (plural).

Zifre and CF, as you know I'm not a native speaker, so it's normal that I don't know colloquial English. If I were a spy, I would get caught. OK, which one is correct; " have enough brains" or "have brains enough"?
Normally we use "enough" before nouns and after adjective and adverbs. Brain is a noun.

As you said, "enough" normally comes before nouns (and this way will always be correct). However, in certain (rare) cases, you can put "enough" after the noun and it sounds more emphatic and interesting. I don't think there is any rule for determining when you can do this, so you're better off sticking with the "normal" way if you can't remember. :-)

So, to answer your question, both are correct in this case.

Sorry, I think I gave you some trouble. Thank you for your explanation.