Anybody using Driven brand HR-2 oil in their slant?

cruiser said
Guys/Gals: My engine builder swears that this is the only oil to use in my newly rebuilt slant six in my 1974 Duster. Completely stock rebuild, not racing or turbo - ing it. Has anyone used this stuff. Pricy at $10.00 per quart. What oil do you use in your stock slanty? I've heard that off the shelf NAPA store brand oil is perfectly okay in these motors.

Thanks - cruiser

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i run their oils in the dart and mustang. is it overkill for my stockish engines? maybe. I'd rather be safe then sorry though. the gp1 has 1200 ppm of zinc in it. I'm sure the hr oil is in that area too. i talked to the driven guys while on sick66. i used to run the hr oil and when i built this motor it was recommended to go to the gp oil. the driven guy (forget his name) who developed their oils said i was much better off with the gp oil.