All the NHRA stock and SS racers as well as some Comp Elininator racers say step headers are worth a little bit of power, ET and MPH on there race cars I seem to remeber someone dyno testing step versus straigh pprimary pipes of the same size as the first step and the steps worked better. The first motor I built and dyno tested made a lot more HP and torque going from a set of Hooker A body fenderwell headers with 1 7/8 primaryys and 3.5 inch collectors to a set of dyno headers thet dyno owner and operator made while my motor was on his dyno, he made them with 2 1/4 primary pipes and 4.0 collectors That motor was a 426 Max Wedge pump gas street motor with 9.5 to 1 compression on CA pump gas back in 1991 or 1992, it was for one of Boyd Coddington cars. That motor made more torque and HP all the way from 3000 RPM up to 6500 RPM when we quit pulling it there as it made peak HP at 5900 to 6100 RPM, depending on the changes we made to the tune up.