Its all dependent on the DA for track times. Up here the Turbos cars rule as they loose less than 1/2 second the SC cars loose closer to3/4 of a second. The N/a cars can loose 1.5 seconds. Examples of 1/4 mile times are a 2010 Mustang GT 15.25,2010 Camaro SS 14.7 an Audi S5 15.2. The EVO and WRX crowds rule the track.I am thinking the 178 mm pulley set is the way to go. Get that SC going much quicker.