not really. People dont seem to care about our Caddies. I mean theres some, but its no Honda 4 banger H22 engine or whatever. Northstar has a few, but it doesn't have a single supercharger out for it yet. We're out smokin mustangs trying to compromise with what we have, while they're able to supercharge the hell out of their cars.
You can always make it go faster by doing universal items-- K&N filter (although not so sure about its effectiveness), exhaust, chips, and even maybe a bolt on NOS system (thats a little ricey for me), but there arent any turbos/supers for them, unless you had it custom made.
Easy enough to do Wes, But in The Peoples Republic of California You'd be hard pressed to get it past the smog check! You've gotta do mods that are hard to spot or are 50 state legal. I like K&N filters although I don't know for sure if they give much of a performance gain. I run them in all my vehicles!
Stock for stock, the torque of the 4.9 is almost identical to the Northstar. I've got a low mileage 4.9 and saw NO immediate difference on the highway with my dad's new DTS! Mind you with 32 valves I guess it is a good deep breather and would probably make more power the faster it goes. PS, torque of the 4.9=275 max vs. North=300 foot pounds.