can a series 2 3800 */c motor use a series 3 supercharger and what needs to be modified for this to work and what would the gain in power be

You talking about a gen5 supercharger? Yes. You will need the lower intake manifold and a adapter to put your throttle body on it.

or you could just use your current lower intake and modify that one just get the gen v gasket trace it the opening on the lower intake and cut it out

ok thanks and what kind of power gains are we talking here i know the gen V has a 20 hp difference in the GP

Give you a little more boost and is more efficient, So 20hp may be possible.

Shouldn't be any more boost.

A Gen 3 M90 pushes the same amount of air as a Gen V M90. The M90 is the amount of air designator. 90 Cubic inches of air per revolution.

http://www.ehow.com/list_7500169_spe...ercharger.html

The benefit of the Gen V is a cooler more efficient 90 cubic inches. This reduces cylinder temps. Aka cooler air, more power.