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Discussion Starter #1 (Edited)
Car is stock except for muffler delete, and IATS relocated to lower air box.

Loade dthe tune up from Evolve, noticed the imediate improvement in response and torque, however a little dissapointed with power up top. Prior to visiting the dyno, I had done about 40miles of mixed driving style, so adaptions should have elapsed. Dyno run below was made when IAT tmeps were 31 deg C (10 Deg C above ambient) the result was 229 kw atw in 4th gear (just a shade over 300hp) Comparing my graph to other M5's the curve on mine is a little less smooth than others, any one experienced this before with their M5 ?

Dyno graph :





You tube clip of first pull done in 5th gear (made 300 whp) coming soon..
 

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The graphs and wheel speeds don't look right. The torque and power curves should cross around 5200 RpM where your graphs are crossing at 2400. Also, what other than a tune has been done? I ask as 825Nm (608 Lb./Ft.) is insane for a N/A motor.
 

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Discussion Starter #5
The graphs and wheel speeds don't look right. The torque and power curves should cross around 5200 RpM where your graphs are crossing at 2400. Also, what other than a tune has been done? I ask as 825Nm (608 Lb./Ft.) is insane for a N/A motor.
Pretty sure that's torque being applied to the roller...
 

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They won't cross at 5252rpm because it is measuring power in kW and torque in nm, not hp and lbft. If you convert it to sae from metric, it will cross at 5252.
 

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They won't cross at 5252rpm because it is measuring power in kW and torque in nm, not hp and lbft. If you convert it to sae from metric, it will cross at 5252.
Yes but unless I am doing the math wrong this chart is claiming numbers that are ridiculous... :confused:

229kw is about 310hp, the converted torque is what, 600+ft-lbs right? Doesn't even make sense.

1hp = ~.735kw
229/.735 = 312hp

1ft-lb = ~1.356Nm
820/1.356 = 605ft-lbs

Is this math? Am I missing something here...? I've been in a car driving for over 10 hours today but I don't see what I am missing. Because torque is only a function of HP, how would these numbers even be remotely possible? HP = torque x rpm / 5252... right?

Maybe the laws of physics are different in New Zealand :)
 

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I am guessing either the scale on the torque is incorrect or, as breakmywindow suggests that is torque applied to roller. Still, whp numbers are down significantly, even accounting for dyno/car variances. Op states he feels the top end is lacking, his dyno numbers support that. Op, have you performed a maf test?
 
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They won't cross at 5252rpm because it is measuring power in kW and torque in nm, not hp and lbft. If you convert it to sae from metric, it will cross at 5252.
The graphs and wheel speeds don't look right. The torque and power curves should cross around 5200 RpM where your graphs are crossing at 2400. Also, what other than a tune has been done? I ask as 825Nm (608 Lb./Ft.) is insane for a N/A motor.
It's the scaling on the graph that's off, metric figures vs english.
 

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Discussion Starter #13
3 runs over layed. The first one done in 5th gear with IAT's @ 42 deg C (20 Deg C above ambient). last 2, the 3rd being highest output done with IAT's 10 deg C above ambient. The waves at the end of the 5th gear run were I'm pretty sure was the rev limiter.

As you can see torque at the wheels reads lower on the 5th gear run. I would ignore the figures. The torque curve seems ok to me.

 

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I recently used some dyno time at Pro Tune in Manukau.. the guys there seemed reasonable and know what they are doing with a car on a dyne. Did you do a before and after dyno to compare?
 

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Discussion Starter #16
I recently used some dyno time at Pro Tune in Manukau.. the guys there seemed reasonable and know what they are doing with a car on a dyne. Did you do a before and after dyno to compare?
mind sharing what your beast made rwkw wise?

Yep late last year at torque performance (different place, same brand of dyno) it made 220.7 rwkw but with iat temps at around 40 deg c. The dyno at torque performance is known to be optimistic so pobably a little under that. The more I drive with the evolve tune the stronger it feels. Maybe my car just needs more time to adapt to the new dme calibrations.
 

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i didn't actually do a power run, diagnosing a misfire - one of the O2 sensors was on its way out as well as at least one of the coil packs. Am waiting on some replacements from Pelican Parts as we speak.
 
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