12-16% loss crank HP to RWHP?
#17
Race Car
I finally tried the Dynojet software for my Dyno runs last spring.
What should people be reporting from their dyno runs? Smoothed/Unsmoothed, SAE/DIN/UNCORRECTED. Should conditions also be reported?
There are a bunch of options for Correction in the Dyno Software:
- UNCORRECTED
- SAE
- DIN
- EEC
- STD
- JIS
Does anyone know of a link that defines all of the different correction methodologies?
So with regard to smoothing and correction factors (as presented by dyno graphing software), what do all of you use when reporting results?
Thanks!
What should people be reporting from their dyno runs? Smoothed/Unsmoothed, SAE/DIN/UNCORRECTED. Should conditions also be reported?
There are a bunch of options for Correction in the Dyno Software:
- UNCORRECTED
- SAE
- DIN
- EEC
- STD
- JIS
Does anyone know of a link that defines all of the different correction methodologies?
So with regard to smoothing and correction factors (as presented by dyno graphing software), what do all of you use when reporting results?
Thanks!
#18
Nordschleife Master
I use smoothing 2 or 3 and DIN. Porsche specs are in DIN. Using unsmoothed data will give a higher number as the data has noise. Lots of folks use SAE.
It is important to say which you used. SAE is a US standard. DIN is German. JIS is Japanese. I believe EEC is European and I don't know what STD is.
Uncorrected is just what the machine saw. If it was a hot day, it'll be lower than expected.
I'll bet you could look up the standards and the conversion factors. The idea is to correct for different conditions in testing. If the temp is cool and the pressure is high the output will be higher. We can't all dyno under the same conditions so the factors help to bring some equivalence to the data.
It is important to say which you used. SAE is a US standard. DIN is German. JIS is Japanese. I believe EEC is European and I don't know what STD is.
Uncorrected is just what the machine saw. If it was a hot day, it'll be lower than expected.
I'll bet you could look up the standards and the conversion factors. The idea is to correct for different conditions in testing. If the temp is cool and the pressure is high the output will be higher. We can't all dyno under the same conditions so the factors help to bring some equivalence to the data.
#19
Race Car
Thanks Glen,
I agree that at least some smoothing should be used. I suspect that most folks use SAE, although if DIN is what Porsche has published for stock numbers, that would provide an additional reference for comparison.
I dynoed in the spring. By removing the noise via data smoothing (which reduced HP by around 2 from the generous unsmoothed ##s) I got the following HP numbers:
271 - 272 SAE Smoothed 5 (highest smoothing factor in the online software)
276 - 277 UNCORRECTED Smoothed 5
279 - 280 DIN Smoothed 5.
I am showing about a 3hp per 100hp difference between DIN and SAE. I also find it interesting that DIN adjusts one direction from UNCORRECTED and SAE adjusts in the other direction.
So If I go to an identical Dynojet, I can use either SAE or DIN to compare to my Spring baseline. I would plan to compare both, but which would y'all rather see?
Thanks.
I agree that at least some smoothing should be used. I suspect that most folks use SAE, although if DIN is what Porsche has published for stock numbers, that would provide an additional reference for comparison.
I dynoed in the spring. By removing the noise via data smoothing (which reduced HP by around 2 from the generous unsmoothed ##s) I got the following HP numbers:
271 - 272 SAE Smoothed 5 (highest smoothing factor in the online software)
276 - 277 UNCORRECTED Smoothed 5
279 - 280 DIN Smoothed 5.
I am showing about a 3hp per 100hp difference between DIN and SAE. I also find it interesting that DIN adjusts one direction from UNCORRECTED and SAE adjusts in the other direction.
So If I go to an identical Dynojet, I can use either SAE or DIN to compare to my Spring baseline. I would plan to compare both, but which would y'all rather see?
Thanks.