Re: AC 43LS Spark plugs

Posted by PackardV8 On 2007/4/17 21:53:50

I am leaning away from the resistor plugs. I've noticed that my Executive wit hthe AL 66 plugs always had a VERY slight rough idle despite many exhaustive attempts to diagnose it. Running timing at 10 degrees BTDC seemed to help both idle and at high speed. Otherwise the car always started and ran fine in all conditions from -10 degrees F to 103 degrees F.
I'm guessing that the resistor plugs causes the rough idle and occasional low speed slight roughness. SMOOTH as silk at 2500-4200 rpm. Advancing the timing probably compensated for the resistence in the plugs ???????????.