How great are they? Well mines got 200k miles on it, uses no oil, runs 160 degrees on the hottest days, and gets 27 mpg on the highway. With a brand new series 2, besides their little quirks, they are one of if not THE best engine GM has ever produced next to the small block. They can handle lots of boost with the proper building of the lower end and will give you excellent feedback when you want it. Look around on the forum on some of these guys cars. Even out there somewhere there'* guys pushing 500hp at the crank with these things.
Gone for good.... Visit www.aurorah.proboards47.com! We have love for bonnevilles!