Rogue, when I first picked up my '89 500, it had the Duncan Eliminator porting package. One of the things they did was completely remove the intake bridge. It ran pretty good but when I wanted more, I took it to Jerry. He did make it clear that he did not recomend this procedure but also blended his dune porting to the previous port job. I'm still on the same piston & ring after almost 2 years of hard riding with no loss of compression.