Those heads as tested were of mixed quality. Some were worn out heads with known issues, others were rebuilt. I do not believe the numbers should be taken for direct comparsion.
I disagree, the numbers are good for comparison. As TOHCan points out, the heads that were tested have very minor defects. I believe it lends more to the authenticity of the chart when these minor defects are pointed out. It shows that each of the heads was put through a qualifying process before testing. The chart shows insight that we can't get from any other source but a dyno. And until someone reputable, like Wallace in this case, does a dyno chart then this is the best thing that has been published. Better than opinion, conjecture, ect. It's an awesome chart that actual testing was documented.
