[J P Stein]

This probably means different things to different people.
To me, it means optomizing engine performance within the manufactures tolerances, while exceeding them where permissible.
Probably the main place this came from was the "good old days"
of heads up drag racing in the "stock" classes.

A couple instances:
The cam profile has a tol of +/- .01 lift......make damn sure yours is + .01 from nominal.

Compression ratio is 9.0:1 +/- .5 ......yours is +.5.

All using factory bits. They'd tear you down to check, also.

Carry hunderds of other parameters out to the Nth degree (all slanted towards performance, none towards longevity) and one can see that this gets expensive in a hurry......thus, these classed died, but not before your basic 283, dual Rochester carbed, Duntov camed engine was pushing out 400 bhp at 8K rpms.....or thereabouts......stock as a stove.

Very little of this goes on any more.......Ask Randy bout the cost of his blueprinted 3.2L.