i have a 71 nova, 350, i keep having a problem with it and cant figure it out without some fresh ideas. My car was running 14s, inital advance was at 21 but thats what it needs, i got it to run a 12. 80 and it pulled real hard by advancing it just from like 19 to 21 initial. i then brought it home after running good times and drove it about a week later, still pulled great, drove it today and its a 14 second car again. I have absolutely not touched anything on it since it ran great, what can be goin on, could it be something in the distributor screwing everything up? possibly carb? what could make it run worse by just starting it up a day later and not touching anything, it sits inside and valves were just adjusted, it will act like this a lot, run slow then just run great for a day or two. It doesnt sit outside so i doubt its water, if anybody gots any ideas let me know if possible, when i shut my car off or start it up could my distributor be moving or anything, let me know if anyone needs more info on the motor. thanks