I was just wondering what the difference is in the series II and series III motor? Do they make there power at different rpms? Which is the preffered motor for tuning?

well if you are referencing the supercharged version it is a more efficient blower and i think different lower intake also other then that I don't know

On the regular it has something to do with little things, lighter parts, Throttle by wire, ect. I do know that series 3 gives off something like 10% the emissions that the s2 does.

I would also think the newer 3800 are designed to use less gas too.

well on the naturally aspirated one they changed the uim from composite to aluminum I think

That they did. I was looking at the drive by wire series 3 a couple of days ago and their intake is now alluminuminuminum.

The L26 does have an aluminum UIM. However, they still use the plastic LIM gaskets.

there are small differences

the L26 (naturally aspirated)
the UPPER intake is alum.
it has a electronic throttle

the L32 (supercharged) has
Forged Connecting rods
Gen V blower
said but not confirmed to have better flowing heads

the Blocks are exactly the same, as alot of other components

the L32 also has drive by wire throttle