Correct dyno procedure for 7spd automatic 722.906?

[algrensan]

Has anyone dyno'd their 7spd automatic 722.906? I have a 2005 SLK350 automatic. I've got K&N filters, Supersprint headers/cats/catback exhaust, and TTP ECU upgrade. Apparently leaving it in drive and getting it up to 4th gear isn't correct way. So after browsing around the forums, I had the shop try switching it into manual mode, set it to 4th gear, and then do a pull above 3500rpms. That seemed to be the right path since the dyno graph was a lot smoother instead of jumping around crazily like before. Dyno mode is enabled. Is the shop doing something wrong or is there something wrong with my car? When we tried manual mode, it was a somewhat consistent 191.8hp (I forget the torque). When we tried auto mode in the past, the numbers were all over the place from low/mid 100s to 220s. I know the SLK is rated at 268hp and 258lb-ft of torque but what should I be expecting at the wheels? Thanks in advance.

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[Green E-300 DT]

Originally Posted by algrensan

Has anyone dyno'd their 7spd automatic 722.906? I have a 2005 SLK350 automatic. I've got K&N filters, Supersprint headers/cats/catback exhaust, and TTP ECU upgrade. Apparently leaving it in drive and getting it up to 4th gear isn't correct way. So after browsing around the forums, I had the shop try switching it into manual mode, set it to 4th gear, and then do a pull above 3500rpms. That seemed to be the right path since the dyno graph was a lot smoother instead of jumping around crazily like before. Dyno mode is enabled. Is the shop doing something wrong or is there something wrong with my car? When we tried manual mode, it was a somewhat consistent 191.8hp (I forget the torque). When we tried auto mode in the past, the numbers were all over the place from low/mid 100s to 220s. I know the SLK is rated at 268hp and 258lb-ft of torque but what should I be expecting at the wheels? Thanks in advance.

If indeed you are dyno testing a vehicle equipped with the 722.9 series seven-
speed transmission, why are you trying to so this using fourth gear?

You should be much better off using direct drive which in your
case is fifth gear which has a direct ratio of 1 to 1.

Your fourth gear ratio is 1:37 which is not direct!

BTW, ditch the K & N air filter.

HTHs