Thank you, Dennis. I am looking for more power/acceleration while passing when I am cruising and pulling my trailer. That will be in the 3500-7000 RPM range (60-90 MPH) I don't need more top speed or to be able to burn the tires. RPM increase is not important to me as I don't approach what I already have. I am now convinced that stage-1 is the appropriate mod for me..... Unless advised otherwise..... Jim