Yup the 97 and up SC'd Regal's and their cousins the GTP Grand Prix (they have the same drive trains and under pinings) can be made to go into the 11's with some pretty easy mods. I have a stock 97 GTP that I bought brand new, and use as my back up driver on rainy days or when the GN is down.
There are also bolt on turbo kits avaialble for them where you basically gut the supercharger and use it's housing as your intake for the turbo system. Installs in a weekend and takes them form their bone stock 15.0 ET to a high 11....