PerfectPower Vs Dynos

PerfectPower Lab Tests

PerfectPower Users Tests

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L5) Mercedes C63 AMG W204 – Yoann

Date: Friday, July 18, 2025

Place: France (27)

PerfectPower: PerfectPower iOS 6.1 – Yoann’s iPhone 14

Dyno: Soft-Engine SuperCar 1200 4×4 synchro of MC-R Performance Normandie (= PerfectPower Lab Rolling Road)

PerfectPower (A) measurement conditions:

• Mode 1 “Accelerometer + GPS” (standard mode in PerfectPower) (only mode available at this time in PerfectPower iOS)
• DIN 70020 standard (engine results corrected for 1013 hPa and 20°C (29.92 in Hg and 68 °F))
• Calculation of losses on parameters (standard mode in PerfectPower) (only mode available at this time in PerfectPower iOS)
• With 2 people on board (Yoann & David) and with full tank
• In 3rd gear in manual mode from 2000 to 7000 rpm (rev limiter)
• With the magnetic mount on ventilation grille (good quality) of Yoann
• Official Result = Average of 4 measurements performed in both directions of the road (direction 1/2/1/2) according to the strict recommendation of PerfectPower in order to eliminate the effects of road slope and wind

Dyno (B) measurement conditions:

• DIN 70020 standard (engine results corrected for 1013 hPa and 20°C (29.92 in Hg and 68 °F))
• Calculation of losses by measure in coastdown (standard mode with chassis dyno) (note: freewheeling at the end of the measurement is possible with this automatic gearbox)
• In 4th gear in manual mode from 2000 to 7000 rpm (rev limiter)
• With 4500 N brake
• Official Result (3 measurements) = Measurement 3 = Measurement with the IAT (intake air temperature) as close as possible to those measured on the road (42-33 degrees)

A) PerfectPower

Comparison of the 4 measurements & Official Result = Average of the 4 measurements

Note: The iOS version currently does neither have the power measurements comparison graph, nor the power measurements averaging graph, nor the function of generation of a new averaged result, but you can still observe on the two screens above:

• The comparison of the 4 power measurements performed in 1/2/1/2 direction
• The averaging of these 4 power measurements which constitutes the official result

In addition, the graph of measurement 2 which is the most representative of the averaged official result is given to you below for graphic illustration.

B) Dyno

Official Result = Measurement 3 = Reference measurement

C) Comparison

Comparaison of results Dyno / PerfectPower:

• Max Power: – 2,0 ch & – 0,4 % (!)
• Max Torque: – 3,6 Nm & – 0,6 % (!)
• Max Power rev: + 179 rpm
• Max Torque rev: + 21 rpm (!)
• Curve shape: Completely identical from start to finish (you be the judge)

Mind-blowing, isn’t it ? Certainly PerfectPower has long proven its exceptional proximity of results with the best chassis dynos, but I recognize as the creator of PerfectPower that it is a constantly renewed pleasure to see results always so spectacular, especially when it is the dyno of a long-time friend like Yoann, who deserves to use a superbly well-calibrated dyno for his work!

But I’ll go even further: it’s important to understand that the true reference in terms of engine results accuracy is PerfectPower, and that we don’t judge the accuracy of PerfectPower by comparing its results to those of chassis dynos, but on the other hand we can judge the accuracy of a chassis dyno by comparing its results to those of PerfectPower!

Of course, you may not agree with this statement, but then you just have to take up my friendly challenge at 10,000 euros & dollars, it is (among other things) there for that!

Note: You can find the detailed report of all these measurements (and even more) in the results report (coming soon) of this Mercedes C63 AMG W204 from the PerfectPower Lab.

Videos of measurement 3 (reference measurement) on the dyno