If you ever run one with the correct curve, you would never lock out or put it at all in by 2,000 again! That's how much is lost! My personal daily driver 66 Mopar 383 4bbl Holley 4200 pounds 2.78 rear gear Factory a/c 20mpg highway while running antique RV2 a/c
Curve is determined by camshaft, compression, and cylinder head design.