Roush 427R engine issue. Troubleshooting..

[WardL]

I'll give you the scientifuc answer to your get what you pay for HP question that applyies to many things. The factory rates the engine at a HP given a set of conditions. It is scientifically impossible to repeat HP checks on an engine HP and get the exact same HP every time it is measured. Measuremnt is usually a bell curve of results. When you retest someting from the factory, it should be within the reproducibility of the test. I don't know what the HP measurement reproducibility is, but it could be something like +/- 25 HP. So on a retest, if you run the exact same test the factory ran, you should get a number +/- 25 of the factory measurement. If you do, then the engine is performing as expected. If you don't, maybe there is a problem or maybe the conditions (temperature, atmospheric pressure, gasoline, etc) are not the same as the factory. Thank goodness everyting is not exact. If it were maybe cops would be giving you speeding tickets for going 0.1 MPH over the speed limit. But Officer, my speedo only said 81 MPH.....