I was told that if you trim off part of the ground electrode on your spark plugs so that the new end of it is half way over the center electrode, you will increase performance, HP, and gas milage. This is supposed to be an old racers' trick. The guy who told me about it is a regular at the local criuse nights, he has a '57 Cheby and just bought a '65 Mustang convertible. He swears by this, does it to all his cars, lawn mower, snow blower ect. Well, since I was doing a little routine maintenence on the 'stang tonight, oil change and plug cleaning, ( I have a little valve seal issue, and until I pull the head out over the winter to get new seals and hardened seats, I clean the plugs like every 400 miles anyway) I decided to give it a try. Well, without touching the gas pedal, there was a noticable difference in the way the car moved out of the garage and down the driveway! Even SWMBO noticed it! Now I don't know if this will cause the plugs to burn out faster or what, but this seem to hold some promise! Have I been missing this all these years? Anyone else try this or heard of it before? Or am I gonna be buying new plugs next week? I need input please!