Usually installing a blower with stock cams is sufficient to raise horse power more than enough to put smiles on everybody's face but if custom cams are a must my first thought is to ask MANY different sources about set up. You may find that with a supercharger the cam timing doesn't have to be all that radical. Cam overlap may not be a great idea with supercharging.
There is a poster on another ferrari site that has already supercharged his 308 with a Wipple style blower underneath a modified injection manifold. Sounds like he has been quite sucessful. Unfortunately I don't remember his name.