I have a 89GT with 5.0 ,Its bored 30 over. .First question....I changed the plugs and stock plugs will not fit my heads . It has 2545 autolights in it .Any one know what heads I have ? Next what should my timing be set at ? When I drive it hard around 4000 RPM the car doesn't want to go for a few seconds then it will. Any idea what that is about ? It has a MSD coil andBox. BBK short headers , anything else you need to know just ask. Thanks....