exhaust manifold cherry red

i was driving to work the other evening and my 84 720 started spitting and spuddering... i got home and popped the hood and the exhaust manifold was cherry red. Is this a sign the converter is stopped up?

most likely ignition module if it has electronic ignition.

catalytic converter, but ive heard of trucks running rich and doin that.

oh really?! Could it be the timing cause it is off and i was messing with it the day before also.

the symptoms you have could be either problem.