Doesn't surprise me one bit. The more holes, the better the vaporization, the more the fuel gets burnt, the more power you make for the same amount of fuel, thus the less throttle you have to use to make the same HP. All this equates to less fuel overall being used, and a bump in fuel economy. I'll bet your idle is smoother, and your on/off throttle transitions are smoother.
I can feel the hood of the car and feel misfires. When I installed bigger injectors on my insight, that are of a significant bigger size (flow rate) and 12-hole vs the 4 hole that stock is, I felt the smoother idle on the hood.
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