[Terry Stapley]

Hi Cobra fanatics, I just replaced the plugs in my 418W after 3000 miles. Upon pulling the plugs I found that the back two on the drivers side on the back one on the passengers side were very black and damp. All other plugs were clean and the porcelin part was a chocolate brown. I have been using autolite # 25 plugs. My question is do I need to go to a hotter plug for those three holes or is my problem something else! I had started the engine and let it idle for about 15 minutes to keep everything operating correctly before I pulled the plugs. Thanks in advance for any ideas and suggestions.