+ 1 Did the exact same thing on my 97' z28 with the lt1 instead of the ls1, and just like posted above. Didn't do a damn thing but change shift points and correct my speedo. I could't tell a difference whatsoever.SCT by FAR. Let me tell you something about hypercrap. i got one for my 1998 z28. it did NOTHING. I felt no difference in power what so EVER. All it said it did was adjust shift points. it don't even add horsepower. its nothing but shift points. they don't have race tunes such as the SCT does. it has none of that.