Originally Posted by MadMaxx
306*.82 (which is 18% loss, ) = 249.28
Within ~3hp of average loss on a automatic, which is 18%. Humidity, dyno type and the age of the engine *DO* play a large role. Also, the super-rich condition of the run doesn't help the total numbers either. The ECU may still be learning, so again...take everything w/ a grain of salt.
Just so we're clear, the caddy 261rwhp mark was done through a manual on a dynajet if memory serves
Anyone who claims they dyno'd 276rwhp (That is 8% driveline loss...pretty much a miracle) on an engine rated at 300bhp is either:
2) had a dyno operator who didn't know what they were doing
The 4.6 in the mustang is not SAE Certified, so it is possible to be underrated some.