12icer
Active Member
I'm with 67 Coronet pull he plugs and have a look. You may have a small insulator crack that opens after it warms, and if you have a few miles on it you may be able to color read them.
I would think it is leaning though and stumbling you may be running along with the throttle just at the transition point from off idle to main jet flow and losing enough velocity in the downstream or be having too much and drawing raw fuel the transition points are the hardest areas to tune, you may have to change the vent sizing to work it out.
As for background on it If you hit the throttle and it does not miss under hard load, all other electrical things being the same I go straight to fuel.
I would think it is leaning though and stumbling you may be running along with the throttle just at the transition point from off idle to main jet flow and losing enough velocity in the downstream or be having too much and drawing raw fuel the transition points are the hardest areas to tune, you may have to change the vent sizing to work it out.
As for background on it If you hit the throttle and it does not miss under hard load, all other electrical things being the same I go straight to fuel.