port & polish, (pros & cons)

[vinj]

Good Question! With the advent of CNC machining of modern engines, even the lower-end engines are flow efficient already. PnP will be more effective with old engines that require headworks and modifications.

The thought entered my mind since a lot of engines are already manufactured with clean-cut machining done to them. On a side note, in the US, blueprinting and the like gives much more gains with the American engines which are based on old designs and built with looser tolerances unlike the modern Jap and Euro engines.

[woodfire]

In the U.S. where hot-rodding is an all time fav, installing high performance crate engines is the norm (e.g. Ford Racing engines, MOPAR Power engines, etc.). In assembling the engine, the hot rodder often installs stroker kits, hence would require machining, blue printing and balancing to max out power potential. Its not unusual to see a small block V8 engine generate 500 to 600 horsepower.

Eleanor, the modern version of the Shelby Mustang GT500, has a Ford Racing crate engine, stroker kit, and optioned with a supercharger (for the Supersnake version). W/o the supercharger, it generates 450ph; w/supercharger, 600+hp.