K & N air filters/rejetting

[wrinklygit]

Hello new world,as a new entrant to beveldom & not as youthfull as I once was,I have started to look at different ways to shed weight on my 79 darmah,any one out there with ideas or experience on replaceing std airbox system with k&n or similar items.As airflow should be increased presumably extra fuel/richer mixture would be req,any performance gains to be had from this route.(Before anyone states the obvious,I have started to diet already).MIKE B.