The idle mixture is not "lean" or "rich"... It is late.... More timing at idle corrects it. 38deg BTDC locked out.
the fuel is burning LATE and burning in the exhaust. More timing at idle corrects this. YOu CANNOT smell a rich or a lean fuel mix but you can smell incomplete combustion. That is the stink and eye sting.
The EGR effect exhaust reversion dilution at idle caused by the big cam overlap slows down the fuel burn speed at idle. So the timing requirement at idle is different than what you are used to.
It needs a lot more idle timing. The locked out distributor allows this.
Now the fuel burns quicker at idle. less reburn in the exhausdt t idle. a lot less eye burn.
Take it outside, Fix the distributor and carb. Drilling is not nessessary.
Lock out the mechanical advance system. Set the locked timing at 38deg BTDC. Then connect the vacuum advance to the PORTED vac adv on the carb.
Make sure the PCV is hooked up and working as designed. This give extra air flow at idle.
Spark plugs: Nothing wrog with NGK but because the setup is wrong it will likely foul the plugs.
Fix it. What is the NGK plug number? What cylinder heads? casting number under the valve cover?
it depends on what heads you got.
Last edited by F-BIRD'88; 05-03-2013 at 01:39 PM.