An Edelbrock Performer (or Performer RPM) will outflow a GT40 style intake on nearly every application with aftermarket heads and a cam. It also allows for some room to keep modding because it will support a lot more horsepower than a GT40 style intake, which are good only to about 400hp without porting (again, under most circumstances, I know it can make more than 400 so don't say I am crazy people with cobra, gt40, explorer intakes). TMoss I believe is a member on stangnet that does porting work on stock lower intakes. You send him your intake, he ports it and sends it back to you. Hope this helps.