Derrick,
On my cross ram tribute car I had always use Champion J-12-Y plugs. I later changed to the NGK R5670, and they worked better, did not foul as much. The car was not raced but street driven to cruises and shows.The biggest improvement to the plugs and over all coming alive performance was switching air cleaners. When the car was on display at a show I would have the stock max-wedge air cleaners. Using the same base I would just switch the element and top, only took a few minutes to do. Like I said the engine came alive, even the idea went up 200 rpm. With this K&N set up plugs never loaded up as I ran rich.
Nick