So first, read this: www.theglobeandmail.com/drive/mobility/article-the-buick-that-beat-a-lamborghini/

After reading, you'll decide you want a Buick Grand National GNX. Used ones may be hard to find, and new ones...well, they don't exist. But they can! Kinda...

So a Grand National is basically a high performance coupe version of a Regal, and the GNX is higher performance still. The heart of the original GNX was a twin turbo V6. Modern Buick Regals are rebadged Opel Insignias with the same 2L turbo 4 as the Chevrolet Camaro, just detuned to 250 horsepowerfrom Chevy's 275hp. The Regal GS is the current performance version of the Regal, again borrowing a Camaro engine, a 3.6L V6 making 310hp (again 25 less than the Chevy version).

In Anakin's words, this is where the fun begins!

So if we were to again borrow a Camaro engine, the next one up is a naturally aspirated V8, which, while cool, isn't a twin turbo V6. Luckily for us, Cadillac makes a twin turbo V6!

Cadillac makes a 3L twin turbo v6 that makes 360 HP which could work...
Regal 250 HP
GS: 310 HP
GNX: 360 HP

So evenish jumps, Cadillac also uses that same turbo 4 but they tuned it down even more to 237 HP, so it's safe to say that the GNX could make 370 for totally even 60 HP jumps between versions.

But is it right? Personally I'd think it best to put the twin turbos on the GS's 3.6L V6, but practically speaking it may not fit.
What are your thoughts? Let me know in the comments!