if the line pressure were too high and was in turn overpowering the seats wouldnt that be eveident when trying to set the float level? I have set the float level with the engine running and had no signs the seats were letting fuel by, ie, fuel coming out of the sight hole. I have never had trouble with pressure before, with a different holley carb, I just cant seem to get the thing to lean out it loads up at idle ferociously almost as soon as the engine is running