I have seen cases were the lid is to Close to the carbs that the carbs pulse hits the lid and that is realy BAD for hp ! One realy good exampel is the stock six pack air cleaner that many beleve has a to smal amount of filter aria so they drop on a taler filter element and that helps alot but what they dont understand is that it isent the filter aria incresment that do good but the fact that the lid comes up a bit !