I'm interested in getting a little more horsepower out of my Volvo Penta 5.0L Gi if possible at a low cost. K&N advertises can single-handedly improve horsepower by as much as 15 percent. I'm used to rejetting motors when adding a K&N. Can/does the fuel injection need adjusting? Has anyone noticed a difference when they added a K&N to a fuel injection system? Is it worth the price ($110 or 59-3364)?<br />Thanks