Wallmart Supertech 10-30. After 10 years, street and strip use, the 350 Chev is worn out so bad, that it cannot be reringed. 91 Geo Metro auto trans, 219k, the topend is worn out, and uses oil. 5 speed overdrive ones seem to do better on topend life. Years ago a 318 Mopar with 166k miles, had 8thou taper in the cylinders, and I reringed it, and put on 50k street, and strip miles. It still ran good, but tried to push the gaskets out, at high rpm. Amc V8 had high Nickle, and Silicon in the blocks, and 200k miles with no ringridge was not unheard of. Are Chev blocks soft, or do I need to use a better oil? Years ago I put rings and bearings in a 413 Mopar 3X, with bracket use, but that may be the limit. Why does Chev need the Crank turned, and Rods resized, and Cylinders bored every time the engine is apart? What kind of life do you get, with the better oil?