See when I done the swap with the stock gap I didn't feel any difference in power at all, didn't even notice anything. After I tried .40 I was sold and felt the gain.mrvax said:My personal experience is that .035 is NO FREEGIN GOOD for a N/A Stang. When I gapped the plugs to the factory setting, the car ran MUCH better. I'm sticking with .053-.057.