[themyst]

I was on a MB forum with a user who lambasted my dyno figures because it was done using an STD correction factor instead of SAE, stating it was more likely along the lines of 390whp instead of 424. I used the STD correction factor in my dyno pulls because every other N54 result on a Dynojet used it. I'm pretty sure if it were 50 degrees like most any other dyno glory run I could have seen higher numbers regardless. I've also heard that SAE correction skews numbers the wrong way due to the fact we have a FI motor vs the performance of NA motors that the SAE correction is based off.

How much difference (if any) would I have seen if I used the SAE correction factor? I do understand that the STD correction factor takes into account optimal conditions, but does anyone have the formula or otherwise to translate my figures into an SAE corrected number?

These guy's claim 425-435whp on a tuned C63 SAE corrected, and all I want to know is the whp difference if I were to have done it using SAE correction.

Thanks in advance!

[Former_Boosted_IS]

Originally Posted by themyst

I was on a MB forum with a user who lambasted my dyno figures because it was done using an STD correction factor instead of SAE, stating it was more likely along the lines of 390whp instead of 424. I used the STD correction factor in my dyno pulls because every other N54 result on a Dynojet used it. I'm pretty sure if it were 50 degrees like most any other dyno glory run I could have seen higher numbers regardless. I've also heard that SAE correction skews numbers the wrong way due to the fact we have a FI motor vs the performance of NA motors that the SAE correction is based off.

How much difference (if any) would I have seen if I used the SAE correction factor? I do understand that the STD correction factor takes into account optimal conditions, but does anyone have the formula or otherwise to translate my figures into an SAE corrected number?

These guy's claim 425-435whp on a tuned C63 SAE corrected, and all I want to know is the whp difference if I were to have done it using SAE correction.

Thanks in advance!

Do you have temperature, pressure, humidity data from the day you dyno'd?

[themyst]

Originally Posted by Former_Boosted_IS

Do you have temperature, pressure, humidity data from the day you dyno'd?

closest I can find is data from dragtimes using the comparison tool which isn't 100% accurate to my area, but close enough. It was 91 ambient in NYC

Englishtown at 2:55 PM on 9/25
87.8 F 43 % 29.82 in

[DefactoM6]

Given the conditions, with SAE correction, you should make more power. You could probably also have the guys at the dyno pull your file, apply the SAE correction (0 the smoothing obviously) and email it to you. Those guys at the MB forum are off their rocker.

[Former_Boosted_IS]

Ideally you would want to start with uncorrected data. With that said, a lot of the internet world uses a 2.6% difference between SAE and STD (SAE is 2.6% lower). SAE corrects to a temperature 77F and 990 mb pressure. STD corrects to a temperature of 60F and 1033 mb pressure. The bottom line is STD averages about 2.6% higher that SAE.

That would mean your 423 rwhp would be about 412 rwhp. Again, these are some small corrections. I personally like uncorrected data.

[DefactoM6]

Whoops, was thinking uncorrected even though I was responding about STD correction. Way to own myself...

[R1000K3]

Originally Posted by Former_Boosted_IS

Ideally you would want to start with uncorrected data. With that said, a lot of the internet world uses a 2.6% difference between SAE and STD (SAE is 2.6% lower). SAE corrects to a temperature 77F and 990 mb pressure. STD corrects to a temperature of 60F and 1033 mb pressure. The bottom line is STD averages about 2.6% higher that SAE.

That would mean your 423 rwhp would be about 412 rwhp. Again, these are some small corrections. I personally like uncorrected data.

+1

The about 10 hp difference figure on a 400 hp level in favor to STD vs. SAE applies for a wide temperature, pressure and humidity range. So it is pretty safe to say STD is normally 10 hp more than SAE corrections at this power level. The corrections are not designed for a turbo engine that is controlled by an ECU that evens out variations so I also normally just look on the actual power, i.e. how much power the car actually made during the test.

The pictures below shows a high power situation when it is cold, dry and the barometric pressure is high vs. a low power situation with high temp and humidity and low pressure. The difference between STD and SAE is about the same in both cases.