Well right now Crawford is one of two aftermarket plenums that can handle boost. The other one would be SSR Engineering who developed and entire new plenum, not just the top half. Since both of them are made from metal as opposed to plastic like Kinetix, they are readily available to handle boost applications. I personally am waiting for the APS tall boy manifold to come out but it looks like it will be a few months before anyone has one in the states. Also there is Kinetix Racing who keeps on saying that they will have a metal intake manifold available, they developed a prototype over a year ago but it did not produce any HP and since then they went to plastic. Now they did say they would have the metal one available in December, but it seems like all they do is talk and don't produce anything. People have been waiting for it over a year and still there is nothing. Well thats all I can think of.