Hi All, I'm new here and I have some questions regarding turbos and horsepower. What's the the advantages and/or disadvantages of having a single or dual (twin) turbo system if they produce similair horsepower? Also, what determines speed, is it horsepower of torque? I know it's a combination of both but I am trying to get an idea of how many hp & torque is required to achieve 0-60 mph in 3.4 secs. Thanks All!