I had a carb issue back in the summer and today had spare time during the race so I changed plugs in the 226. Number 1 looked a little fouled the other 5 looked ok but it definitely runs a little stronger with new plugs. I also swapped out carbs to a carb I just rebuilt and dialed in my mix screw. I think today was the best it has started in a while and while idling in the garage, it didn't spray black soot all over the floor out of the tail pipe. I think I have been running rich so I backed the idle mix screw out until it just started to run a little rough and then turned it in slightly.

Anyway, when I took the plugs out there was no way they were at the 24lbs I torqued them to when I put them in. I cranked the new ones up to 26lbs. I know I have read to retorque head bolts after a rebuild but does the same hold true for spark plugs?

JB

 

New plugs have new, uncrushed seal washers and it's pretty normal for them to relax a little. A re-torque is a good idea.

On the carb mixture, I think you'll get better performance and economy turning a 1/4 turn out from where it stumbles on the lean side (screwing them in). With my air/fuel monitor I can see the difference, lean stumbling happens when you are in the high 13's/low 14's, on the "rich roll" side it can be down in the 10's, way too rich. On Holleys the idle jets affect part throttle mixture quite a bit, up until about 1/4 throttle.