Joined Hybridz, and just got my Z car today.
I built a nasty all alloy supercharged 4.6 for my 97 Cobra a few years ago and had crazy HP, basically fell in love with DOHC Modular motors.
For the 280Z I will be doing a NA Cobra motor (2001 Cobra), 300 HP in the Z will be fine I figure.
Looks like it's been done here (notheredave, yellowoctupus, and mitchnandy) so I will need to tap into their experience.