Ok, here is the situation, the LG4 in my 86 SC is old, lotsa miles, but has lots of pep left in it. However, it knocks like a SOB. At least i think its a knock. Anything over half throttle and i start to hear some kind of chattering. Only when it is in gear, regaurdless of how high the octane in it, the timing, i had it around 6-8*advance , so i backed it down to zero- 1*retarded, cant tell exactly, the numbers are worn off the marker. Made no diffrence whatsoever. So i put it back to where i had it. This is driving me nuts and i know it cant be good for the motor, any help would be greatly appreciated.

 

excess carbon buildup maybe? have you tried top end cleaner or simplay misting water into the carb/throttle body to steam clean it?

 

Sounds like a good idea. I will give that a try. Thanx for the help, happy holidays.