hmmmmm...there's an idea. i've been trying to work out the possibilities of making some sort of 16v 4age-gze hybrid motor, but this 20v gze idea doesnt sound half bad.
i'm assuming that the 20v isnt mapped for boost, so you would have to run either a microtech (or some other EMC) or a super afc with it
good luck with the project steve, (if indeed such a project is to take place)