I noticed that the outside of the spark plugs were changing colors on the head of my engine. The rear plugs are starting to get a wet black buildup around the outside and the front ones are starting to get the burnt marshmellow or tan color on the outside of the plug. What does this mean? Do I have a leak somewhere? Is their too muhc compression? Maybe the valve lash isn't set right?
Thanks

sounds like carb trouble or too much low rpm cruising or short trips put in freash plugs and go hammer the car at least 10 times 0 to65 and check the plugs and tell me what you see

Hi,
Is that a good idea? I've only got like 200 miles on the engine since the cam break-in after rebuilding it.
Thanks

Turned out to be a header leak. Fel-Pro isn't living up to their reputation.