With current epa regulations, I understand it may be tough, but besides Quaker State defy, brad penn (pricey) and Valvoline Racing (unsure if available in 5-30, unsure about how long an oci) what other commonly available high zinc oils are available in these grades? I know opinions vary on how necessary zddp is, but I am weighing my options for a flat tappet engine. Defy seems like the logical choice, but I dont have any leaks or consumption and dont really like the idea of using a "high mileage" oil in an engine that doesnt need it.
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