I had recently put a descent rebuilt 350 in my '69. After about 8,000 miles, it started burning oil and severely fouling the plugs with carbon buildup. I burned 6 quarts of oil and two sets of plugs on a trip from Daytona Beach to Louisville, KY. The strangest but maybe the most reasonable answer I got from one mechanic was that because I had a Edelbrock carb (which he said was junk) it was pouring too much raw gas into the cylinders and washing the oil from the cylinder walls and rings. This kept the rings from seating and allowing oil blow by. The strangest part is there is no tail-pipe smoke at all! None blue or black! I had previously never heard of this. Does this make sense to anyone?