264 112lc advanced 4deg, i think the problem is in fact the flex plate, i ran 110 oct fuel and no change, i bought a stethoscope and did not find any noise coming from the timing chain, the engine was not pinging like i thought it was but, i did find a lot of noise coming from the inspection cover, i removed it and i seen sparks flying off the flex plate, the noise was much louder. the engine is running perfectly, it must be the flex plate