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    Question Cobb AP "Torque Output" Paramenter

    Is it accurate for crank torque ?

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    Click here to enlarge Originally Posted by BuraQ Click here to enlarge
    Is it accurate for crank torque ?
    The numbers it shoots out for me are absurdly high.
    E88 N54 Alpinweiss/Coral Red/Motiv HTA 3586r Tial .82AR/Motiv Port Fuel/BMR 3.5" Exhaust/ER CP/Synapse/VRSF FMIC/Rob Beck PCV Valve + Cap/ST Coilovers/M3 FCA + Tension Rods/M3 Subframe Bushings/M3 FSB/AA Strutbrace/DINAN Camber Plates/Apex ARC-8/Project Kics/VAC Hubs/Rogue Transmission Mounts/Alpina TCU Flash/Icarbon/Kerscher/BMW Performance
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    I don't think so. I think it's come calculated number which is fine as long as all the torque limit tables are in the same ballpark.

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    I couldn't seem to change it to ft/lbs. Or am I dumb? lol
    2007 Jet Black E90 335xi "The Mistress" / PTF-Cobb / E50 / FuelitS2 / 5" Stepped FMIC / Synapse BOV and Charge Pipe / Alpina Flash / Muffler Delete w/ 4in Black Tips / DCI / 19x8.5 Satin Black Squared Enkei Raijins / 245/35/r19 Bridgestone Potenza S04 Pole Position / 20mm Rear Spacers / 2 10" Rockford Fosgate's Added to Logic7 (15 total speakers!)
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    Can't speak to the accuracy as I don't own a COBB, but most of the DME torque calcs are in N*m. Multiply your results by 0.7376 to get ft*lbf.

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    Click here to enlarge Originally Posted by EvanL Click here to enlarge
    Can't speak to the accuracy as I don't own a COBB, but most of the DME torque calcs are in N*m. Multiply your results by 0.7376 to get ft*lbf.
    "Torque Output" shows 840.4 nm, so using your equation 840.4 * 0.7376 = 619.87 ft lb ?

    Humm I think thats too high, lol, I need to get this thing dynoed for real

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    Click here to enlarge Originally Posted by BuraQ Click here to enlarge
    "Torque Output" shows 840.4 nm, so using your equation 840.4 * 0.7376 = 619.87 ft lb ?

    Humm I think thats too high, lol, I need to get this thing dynoed for real
    Read back to your first post...crank torque. Divide by 1.17 (value pulled out of my ass, I have no idea what driveline loss is for the N54 drivetrains) to get a more somewhat more reasonable wheel torque value.

    619.9 ft*lbf / 1.17 = 529.8 ft*lbf at the wheels. Still high for stockers, but a more consistent baseline than VirtualDyno for comparison's sake.

    Further thought makes me wonder if the value COBB is giving you is the DME calculated theoretical torque, i.e. without internal engine friction and parasitic heat losses. That would be enough to explain the remaining "bonus" power in the data.

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    Click here to enlarge Originally Posted by EvanL Click here to enlarge
    Read back to your first post...crank torque. Divide by 1.17 (value pulled out of my ass, I have no idea what driveline loss is for the N54 drivetrains) to get a more somewhat more reasonable wheel torque value.

    619.9 ft*lbf / 1.17 = 529.8 ft*lbf at the wheels. Still high for stockers, but a more consistent baseline than VirtualDyno for comparison's sake.

    Further thought makes me wonder if the value COBB is giving you is the DME calculated theoretical torque, i.e. without internal engine friction and parasitic heat losses. That would be enough to explain the remaining "bonus" power in the data.
    Your driveline loss calculation is on par with mine. I calculated it at 15% driveline loss after the crank before the wheels. Also the DCT has no torque converter like the AT do if that matters.
    @Josh@Cobb can you give us some insite of how accurate this paramter is in calculating torque and how it is coming it with its numbers ?

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    Click here to enlarge Originally Posted by BuraQ Click here to enlarge
    Your driveline loss calculation is on par with mine. I calculated it at 15% driveline loss after the crank before the wheels. Also the DCT has no torque converter like the AT do if that matters.
    @Josh@Cobb can you give us some insite of how accurate this paramter is in calculating torque and how it is coming it with its numbers ?
    The torque is calculated in the DME based on modeling done internally. It should be reasonably accurate until you start messing with load to torque tables or anything else that would start to skew the calculations. At that point you may be making it more accurate for your setup or completely ruining those calculations. If the car is running well with just a flash, those values should be pretty good since they are used for quite a bit of the DMEs requests.
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    Click here to enlarge Originally Posted by Josh@Cobb Click here to enlarge
    The torque is calculated in the DME based on modeling done internally. It should be reasonably accurate until you start messing with load to torque tables or anything else that would start to skew the calculations. At that point you may be making it more accurate for your setup or completely ruining those calculations. If the car is running well with just a flash, those values should be pretty good since they are used for quite a bit of the DMEs requests.
    Yes understood, the current sample map being referenced in the OP the Load to Torque Limit table's "Y axis'' was reverted back to stock in the OTS E30 map, the base values remained untouched which are stock values.

    Further more, the "Requested Torque Limit (Driver)" was increase by about 12%, all other torque table calibrations remained untouched in the OTS E30

    This being said, are these changes enough to cause a deviation from the true numbers ?

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