Cadillac magazine reports a twin turbo V/6 making 420 HP for 2011 CTS.

Possible, but far out.

From now on, with the constantly stricter CAFE fuel mileage standards, GM and others are going to be doing a LOT of smaller displacement turbo/supercharged engines for everything, rather than just more displacement and cylinders. Proof of that is how the current Direct Injection 3.6L finally nailed the coffin on what was to be the all new "Ultra" OHC V8 to replace the Northstar.

So, yeah, something like that is definitely possible and even probable, in one of a variety of forms.

How about retrofitting one in my 2008 ? ;)

2011? errrr....

This should have been an offering in 08 or EARLIER.

Look at it like this in terms of performance:

Base CTS > Base 3 or 5 Series BMW
?? < Midgrade 3 or 5 series (335xi, 545i, etc.)
V Series > M Series

So, in terms of speed and power we are killing Bimmer at the low end and high end but getting raped in the middle. Cadillac needs a 350 to 450hp setup.

Like this
Base CTS= 255 or 304
Sport CTS= 400hp SCed 3.6
CTSV= 550+ hp

Hopefully my CTS will be SCed before 2011 anyway.

Just my thoughts on the subject. :D