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The bottom line is: we coulda done better. Or so we learned after we placed a call to Total Seal and discussed our results. If we had increased the high-speed air bleed size (arrows), effectively leaning out the top end of the fuel curve, we wouldn't have lost the power up there, says Total Seal. Their testing has shown gapless rings pull more vacuum at higher rpm and therefore will also pull more fuel causing the engine to run rich at the top end. A review of our fuel curve confirmed this to some extent, but we didn't see a huge difference in the Lambda Air/Fuel readings from low to high rpm, so we never thought to change the air bleeds. Also, Total Seal recommends running less ignition advance with gapless rings, because peak cylinder pressure comes just a bit sooner and therefore the combustion process begins that much quicker. Unfortunately, the engine was off the dyno before we could test either of these theories. But, we trust the information from Total Seal and have no reason to doubt its validity.