Just thought id shed some light on the GTP's since i own one.

97-03 GTP's are supercharged with an eaton M90 gen3 240hp
04 GTP are supercharged also with an m90 but gen 5 260hp
97-?? Buick Regal (i forget which model) M90 gen 3 240hp
97- 03 Bonneville SSEI Model comes with a M90 gen 3 240hp
04 Impala SS M90 Gen 3 240hp

Stock the GTP runs about 15.0 (including the 04)
All the others are about 15.5 because they weigh more.

The whine is from the GTP. It does have work done to it! Stock GTP's you would never really hear the whine, with a cold air package they sound like the one in the video or a ford lightning for that matter.

your more likely to run into a N/A GM car than a supercharged one as they seem to be pretty rare. Also, there probibly one of the most expencive cars to mod, as only a few companies make parts.

Hope this helps, Brent