Cheap alternative to pricey flat tappet oil in street cars...

Dave,

I did a quick and dirty spreadsheet to compute how much lucas break in you'd need to put in with a std shelf oil assuming the lucas has that Zn and Ph content. Here are some numbers that makes your solution an even better choice.

Shelf oil with 1000 PPM of each requires ~.3 Qt of Lucas in a 6 Quart oil change to reach the desired high end numbers you posted.

If the shelf oil has 800ppm of each, the Lucas required is ~.5 qt.

That makes the solution even less expensive.