Quote:
Originally Posted by EMPOWERD
Nice numbers Sia! Was that SAE or STD? Smoothing?
|
This is just a quick reference about SAE and TSD.
Quote:
“(SAE:
"SAE (Society of Automotive Engineers), USA. Power is corrected to reference conditions of 29.23 InHg (99 kPa) of dry air and 77 F (25°C). This SAE standard requires a correction for friction torque.
STD:
STD is Another power correction standard determined by the SAE. Power is corrected to reference conditions of 29.92 InHg (103.3 kPa) of dry air and 60 F (15.5°C). Because the reference conditions include higher pressure and cooler air than the SAE standard, these corrected power numbers will always be about 4 % higher than the SAE power numbers. Friction torque is handled in the same way as in the SAE standard."
Here is some quick math (using assumptions and round numbers):
STD:
Air Temperature: 60F
Absolute Pressure: 29.92 inches Hg
Relative Humidity: 0%
Relative Horsepower : 104.8%
Air Density: 1.223kg/m3
Relative Air Density: 99.8%
Density Altitude: 67feet
Virtual Temperature: 60F
Vapor Pressure: 0 inches Hg
Dyno Correction Factor: .955
SAE:
Air Temperature: 77F
Absolute Pressure: 29.23 inches Hg
Relative Humidity: 0%
Relative Horsepower : 100%
Air Density: 1.157kg/m3
Relative Air Density: 94.4%
Density Altitude: 1952feet
Virtual Temperature: 77F
Vapor Pressure: 0 inches Hg
Dyno Correction Factor: 1)”
I am not sure it was to busy to ask the technician, but you should know, weren’t you there?