The strange thing we noticed, when comparing the Wix 51515 to the Wix racing 51515R filter at the dyno ; the racing filter actually had Slightly SMALLER openingson the filter base plate. That did not make sense to us nor the dyno/shop owner.

Anyone have a clue as to why that would be?


1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.