Because exhaust timing is raised - defefnetly run time will go down. On speed type of race ( tether boats and cars,c/l airplanes) it is realy doesn't metter-there is no limitation on tank-just show max speed. In our case we got to be very carefull. Raising timings on exhaust and transfer events ( up to ertain) ammount) will help to pull out more power, but it will also reqiured to work out pipe, gearing etc.-it is different kind of power.