Re-dyno: Stock M2C

McLaren720s · 04-09-2020, 04:50 PM

First dyno - 425 whp, car in dyno mode, notice the bad power curve with huge drop off after 5500rpm, fan was not on the first run

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Second dyno - different shop - 377whp, car NOT in dyno mode, notice the nice smooth power curve without drop off after 5500rpm

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I don't know which dyno result to trust now. 50whp difference between dyno runs is a lot but much healthier power curve at the second shop and on par with other dyno results i've seen in terms of curve..

Does it matter that for the second dyno the car was not in dyno mode?
Brian from Kies Motorsports was saying in one of his videos that if the car is not in dyno mode, it "may" limit power due to the car "freaking out" being on rollers with wheels spinning at different speeds. I also did get a bunch of errors during the run.

infinitekidM2C · 04-09-2020, 05:34 PM

This is why dyno's are only good for before and after tune analysis. Dyno to dyno is a crap shoot.

McLaren720s · 04-09-2020, 06:49 PM

Quote:

Originally Posted by infinitekidM2C

This is why dyno's are only good for before and after tune analysis. Dyno to dyno is a crap shoot.

Agreed, only reason I got a second one is because the power curve on the first one looked really bad and wasn’t sure if the car has issues or it was the dyno.

M2C_OZ · 04-09-2020, 08:38 PM

Quote:

Originally Posted by McLaren720s

First dyno - 425 whp, car in dyno mode, notice the bad power curve with huge drop off after 5500rpm, fan was not on the first run

Attachment 2280280

Second dyno - different shop - 377whp, car NOT in dyno mode, notice the nice smooth power curve without drop off after 5500rpm

Attachment 2280285

I don't know which dyno result to trust now. 50whp difference between dyno runs is a lot but much healthier power curve at the second shop and on par with other dyno results i've seen in terms of curve..

Does it matter that for the second dyno the car was not in dyno mode?
Brian from Kies Motorsports was saying in one of his videos that if the car is not in dyno mode, it "may" limit power due to the car "freaking out" being on rollers with wheels spinning at different speeds. I also did get a bunch of errors during the run.

This is my dyno sheet

Mustang dyno
Car on dyno mode
Untuned

BAN_M2C · 04-10-2020, 11:39 AM

Hasn't it been proven that the M2C has a flat line after 5500 just to make sure it doesn't break big brothers legs?

You tune and that flat line goes away..

Commanderwiggin · 04-10-2020, 11:58 AM

It's best to use the same dyno for delta comparisons. Also Dynojets "IMO" are the best as they can't be easily manipulated like a mustang. Dynocom read higher from most I've seen. Regardless it's just a tool.

See my dyno comparison before/after tune at the end of this vid:

ONLYA6 · 04-10-2020, 12:36 PM

I can concur Dynocom's read very high. I won't waste my time on those anymore.

DynoJet is a good "standard" for comparison. Just make sure the numbers are displayed in SAE calculations. STD calculations tend to fluff numbers slightly due to the correction factor.

mike@x-ph.com · 04-10-2020, 01:37 PM

Quote:

Originally Posted by infinitekidM2C

This is why dyno's are only good for before and after tune analysis. Dyno to dyno is a crap shoot.

+1

McLaren720s · 04-10-2020, 03:15 PM

But the point was, would the car not being in dyno mode lower the reading?

Got f1? · 04-10-2020, 03:27 PM

Quote:

Originally Posted by McLaren720s

But the point was, would the car not being in dyno mode lower the reading?

I don't know the answer definitively but I would assume it would make a difference given they went through the trouble to include that setting. Would love to know for sure.

robertm · 04-10-2020, 03:35 PM

How does one set dyno more?

McLaren720s · 04-10-2020, 03:47 PM

Quote:

Originally Posted by robertm

How does one set dyno more?

SeanWRT · 05-03-2020, 12:17 AM

Different dynos read vastly different.

There is absolutely no value to do any other dyno than dynojet if you don't do before and after.

Dynojet reads high albeit not the highest, but the point is it reads most consistent across different conditions, by far.

M2C puts down 370-380whp stock on dynojet (DCT on the higher end), which sounds correct.

M Fifty · 05-06-2020, 12:47 PM

Any dyno that gives consistent results is useful in tuning an engine. You do a Before, make an adjustment, then do an After. Iterate until happy.

Everything else is just Bragging Rights.

OP, that first plot just looks like the ecu was backing things off as the temperatures rose. The blue and green traces look good.

04-09-2020, 04:50 PM	#1
McLaren720s Major 1475 Rep 1,286 Posts Drives: 2024 M4 Competition X Join Date: Jun 2019 Location: Seattle iTrader: (0)	Re-dyno: Stock M2C - HUGE discrepancy First dyno - 425 whp, car in dyno mode, notice the bad power curve with huge drop off after 5500rpm, fan was not on the first run Second dyno - different shop - 377whp, car NOT in dyno mode, notice the nice smooth power curve without drop off after 5500rpm I don't know which dyno result to trust now. 50whp difference between dyno runs is a lot but much healthier power curve at the second shop and on par with other dyno results i've seen in terms of curve.. Does it matter that for the second dyno the car was not in dyno mode? Brian from Kies Motorsports was saying in one of his videos that if the car is not in dyno mode, it "may" limit power due to the car "freaking out" being on rollers with wheels spinning at different speeds. I also did get a bunch of errors during the run. __________________ 2024 BMW M4 Competition XDrive - Tanzanite Blue/Kyalami Orange - AST HAS - RaceChip Last edited by McLaren720s; 04-09-2020 at 04:58 PM..
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04-09-2020, 05:34 PM	#2
infinitekidM2C Major General 4206 Rep 5,728 Posts Drives: 2019 M2 Competition Join Date: Nov 2007 Location: Orange County, CA iTrader: (4) Garage List 2019 M2 COMPETITION [9.50] 2008 135i (my old car) [7.39]	This is why dyno's are only good for before and after tune analysis. Dyno to dyno is a crap shoot.
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04-10-2020, 11:39 AM	#5
BAN_M2C Brigadier General 4178 Rep 3,075 Posts Drives: 991.2 Porsche GT3, BMW E46 M3 Join Date: Jul 2016 Location: Sunshine State iTrader: (5) Garage List 1987 BMW 325is [10.00] 2004 BMW X3 [6.50] 2018 Porsche 911 GT3 [10.00] 1974 BMW 2002tii [10.00] 2004 BMW M3 [10.00]	Hasn't it been proven that the M2C has a flat line after 5500 just to make sure it doesn't break big brothers legs? You tune and that flat line goes away.. __________________ Follow me on IG Garage: 2018 991.2 GT3\|2013 135i\|2004 M3\|2004 X3\|1987 325is\|1987 325i\|1974 2002tii
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04-10-2020, 11:58 AM	#6
Commanderwiggin Major 2048 Rep 1,200 Posts Drives: M2C - X3M - Turbo E46 M3 - 45E Join Date: Mar 2014 Location: SOCAL iTrader: (2)	It's best to use the same dyno for delta comparisons. Also Dynojets "IMO" are the best as they can't be easily manipulated like a mustang. Dynocom read higher from most I've seen. Regardless it's just a tool. See my dyno comparison before/after tune at the end of this vid: __________________ 575RWHP F87 M2C - ECUTEK RACEROM with flex fuel tuning by Bend Calibration 1000+RWHP E46 M3, Lab22 Built Turbo S54, Bend Calibration Tuned - BMW Half Mile Record Holder
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04-10-2020, 12:36 PM	#7
ONLYA6 Second Lieutenant 217 Rep 210 Posts Drives: '20 X3M '19 M2C Join Date: Mar 2016 Location: West Virginia iTrader: (0)	I can concur Dynocom's read very high. I won't waste my time on those anymore. DynoJet is a good "standard" for comparison. Just make sure the numbers are displayed in SAE calculations. STD calculations tend to fluff numbers slightly due to the correction factor. __________________ 2020 X3MC, 2019 M2C '14 F-150 Tremor, '99 Mustang Turbo
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04-10-2020, 03:15 PM	#9
McLaren720s Major 1475 Rep 1,286 Posts Drives: 2024 M4 Competition X Join Date: Jun 2019 Location: Seattle iTrader: (0)	But the point was, would the car not being in dyno mode lower the reading? __________________ 2024 BMW M4 Competition XDrive - Tanzanite Blue/Kyalami Orange - AST HAS - RaceChip
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04-10-2020, 03:35 PM	#11
robertm Major 450 Rep 1,358 Posts Drives: 2020 M2 Comp Join Date: Oct 2007 Location: dfw iTrader: (0)	How does one set dyno more?
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05-03-2020, 12:17 AM	#13
SeanWRT Colonel 3179 Rep 2,577 Posts Drives: E90 M3 & F87 M2 Join Date: Sep 2015 Location: Shanghai iTrader: (1)	Different dynos read vastly different. There is absolutely no value to do any other dyno than dynojet if you don't do before and after. Dynojet reads high albeit not the highest, but the point is it reads most consistent across different conditions, by far. M2C puts down 370-380whp stock on dynojet (DCT on the higher end), which sounds correct. __________________ Lemania 2320
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05-06-2020, 12:47 PM	#14
M Fifty Banned 844 Rep 1,962 Posts Drives: M2 & 330CI Join Date: May 2018 Location: The Interweb iTrader: (0)	Any dyno that gives consistent results is useful in tuning an engine. You do a Before, make an adjustment, then do an After. Iterate until happy. Everything else is just Bragging Rights. OP, that first plot just looks like the ecu was backing things off as the temperatures rose. The blue and green traces look good.
	Appreciate 0 Quote