If you're breaking in a new engine or running an older flat tappet camshaft setup, the Lucas Oil 10063 additive is like giving your motor a VIP treatment. I’ve used this in everything from vintage muscle cars to small lawn mower engines, and it consistently delivers smoother break-ins and reduced wear.

The zinc-rich formula is a lifesaver for flat tappet cams—no more worrying about premature lobe wear. I added it to a fresh Mopar build, and the difference in valve train noise was noticeable immediately. Dyno-tested? Absolutely feels like it.

One minor gripe: the 16-ounce bottle could be bigger for frequent users (I go through about 4-5 oz per small engine). But at $7 cheaper than AutoZone? Worth stocking up. Pro tip: Don’t overuse it—zinc is for break-in only. I swapped to regular oil after 1,000 miles on my GMC V8.

Final verdict? Whether you're saving a warranty-bound generator or reviving grandpa’s Chevy, this amber liquid is mechanical insurance. Smoother rings, happier cams, zero regrets.