I would consider which build would be the more economical and still provide the best/most bang for the buck. Using the Brazilian head will require custom pistons to tailor the compression to be suitable for boost, as well as the added cost and expense of a sheetmetal intake. Those two items alone will make the cost of using that head considerably more than using a siamese head which will probably be the better head to start with anyway and allow you to use lesser expensive pistons and more intake choices. I don't think the Brazilian head will really give you any advantage over the siamese head as far as HP output, just cost more money for less gain.
What was your main reason for selecting the Brazilian head over the siamese head to begin with.
