saw this info posted on a turbo omni site, most of it should be relevant here??
How do you read your spark plugs? Here are some guidelines. Install a new set and then go for one WOT pass down a back road. Now pull each one out (be careful not to burn yourself!) and look very closely. You want to see sharp corners on the electrodes and no "salt & pepper" on the center porcelain insulator (salt = tiny melted aluminum globs, pepper = carbon deposits that have "splashed" onto it). If the electrodes have sharp corners before a run and rounded corners afterwards, you're probably lean; add fuel. Salt and/or pepper is probably from detonation; retard timing, or lower compression. Cracked porcelain is definitely from detonation; retard timing, or lower compression significantly (such as with a headsaver gasket by Fel Pro). Real dark porcelain = too rich; take some fuel away. Grey porcelain = good; yellow porcelain = gasoline additives; rust-colored porcelain = 104 octane booster.
the info comes from a fellow named dempsey bowling, i highly recommend his page if youre ever searching for 80's mopar info. just do a google search for dempsey bowling, there arent too many people with his name.
