The dipstick that I bought my car from put Autolite 24's in the heads instead of the Autolite 3924's that AFR spec's. I've been having problems when the car warms up and my track times were pretty mediocre last night. If the shank of the sparkplug is too short, so the electrode is shrouded by the sparkplug hole, what would/could happen? If the car would even run how would it be affected?
