2020 m5c top speed mystery

imyy4u · 04-13-2022, 03:17 PM

So...I was doing a top speed run in a safe area, and I topped my car out at 182mph. GPS verified I was at about 180mph or so. I have a stock 2020 M5C.

How is this possible? I don't have the M Driver's Package. I bought my car used but I don't think it has ever had a tune. GPS verified I was doing about ~180mph when fuel cut off. I do have non-stock wheels, but I have 20" tires that are the exact same size (285/30 R 20) so I am assuming wheels must also be the same.

Only thing I can think of is that this car was sold with 285/35 R 19 and a previous owner put 285/35 ZR 20 on which could account fof a 6mph speed difference...but reading my VIN it looks like my car was sold with 20" wheels/tires. And this also doesn't explain why the 155mph limit is gone...

Thoughts? Ideas?

imyy4u · 04-13-2022, 03:18 PM

wrong forum...mods, feel free to move.

pbonsalb · 04-13-2022, 05:16 PM

Check your idrive to make sure the correct size tires are selected. I doubt this is an issue since the diameters of all factory approved tires should be the same (19”, 20” and 21”). The tire sidewall is reduced as the rim diameter is increased.

No other ideas. Not sure whether the speed limiter is coded out or can only be deleted as part of a tune.

M5KEITH · 04-13-2022, 07:02 PM

If you bought car used I am sure it had a tune and speed limiter was removed. Otherwise you would have hit limiter at 163 MPH on speedo which is 160 MPH. The speedometer is off by 3 miles per hour.

imyy4u · 04-17-2022, 10:03 PM

Quote:

Originally Posted by M5KEITH

If you bought car used I am sure it had a tune and speed limiter was removed. Otherwise you would have hit limiter at 163 MPH on speedo which is 160 MPH. The speedometer is off by 3 miles per hour.

Hmm...ok. That's disappointing, honestly. I was hoping it had no tune. Is it possible all they did was remove the speed limiter with the tuner, or do you have to put a custom tune in order to do that?

Also...why limit to 182/183mph? That makes no sense at all to me...shouldn't it be 189mph?

m5_mbb7 · 04-29-2022, 06:17 AM

M drivers package will let you top out at 193. Stock should top out at 163. I know that BMW has different numbers but this is my personal experience. You need to flash a car in order to remove the speed limiter so it has certainly been tuned and the warranty is probably void if it has.

But the speed limiter topping out at 183 is weird I agree. No idea why that would be the case. What gear and rpm is the car in at that speed?

RobRed · 05-03-2022, 05:24 PM

there have been examples that don't adhere to the stated electronic limiter at 155/163 the car is capable of 190mph when the limiter is off.

i have friend who is s feature editor at a major car mag and they regularly see examples of this. the 155 limit was a friendly limit set by manufacturers.

i wouldn't be too concerned over this and it doesn't mean the car for sure has a tune.

04-13-2022, 03:17 PM	#1
imyy4u Private 50 Rep 53 Posts Drives: 2020 M5 Comp Join Date: Feb 2022 Location: Chicago iTrader: (0)	2020 m5c top speed mystery So...I was doing a top speed run in a safe area, and I topped my car out at 182mph. GPS verified I was at about 180mph or so. I have a stock 2020 M5C. How is this possible? I don't have the M Driver's Package. I bought my car used but I don't think it has ever had a tune. GPS verified I was doing about ~180mph when fuel cut off. I do have non-stock wheels, but I have 20" tires that are the exact same size (285/30 R 20) so I am assuming wheels must also be the same. Only thing I can think of is that this car was sold with 285/35 R 19 and a previous owner put 285/35 ZR 20 on which could account fof a 6mph speed difference...but reading my VIN it looks like my car was sold with 20" wheels/tires. And this also doesn't explain why the 155mph limit is gone... Thoughts? Ideas?
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04-13-2022, 03:18 PM	#2
imyy4u Private 50 Rep 53 Posts Drives: 2020 M5 Comp Join Date: Feb 2022 Location: Chicago iTrader: (0)	wrong forum...mods, feel free to move.
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04-13-2022, 05:16 PM	#3
pbonsalb Lieutenant General 5234 Rep 10,616 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Check your idrive to make sure the correct size tires are selected. I doubt this is an issue since the diameters of all factory approved tires should be the same (19”, 20” and 21”). The tire sidewall is reduced as the rim diameter is increased. No other ideas. Not sure whether the speed limiter is coded out or can only be deleted as part of a tune.
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04-13-2022, 07:02 PM	#4
M5KEITH Second Lieutenant 130 Rep 214 Posts Drives: M5 Join Date: Jan 2021 Location: Massachusetts iTrader: (0)	If you bought car used I am sure it had a tune and speed limiter was removed. Otherwise you would have hit limiter at 163 MPH on speedo which is 160 MPH. The speedometer is off by 3 miles per hour.
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04-29-2022, 06:17 AM	#6
m5_mbb7 Lieutenant 223 Rep 423 Posts Drives: M5CS, M5C, M2C Join Date: Oct 2021 Location: LA/OC/SFBA iTrader: (3)	M drivers package will let you top out at 193. Stock should top out at 163. I know that BMW has different numbers but this is my personal experience. You need to flash a car in order to remove the speed limiter so it has certainly been tuned and the warranty is probably void if it has. But the speed limiter topping out at 183 is weird I agree. No idea why that would be the case. What gear and rpm is the car in at that speed?
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05-03-2022, 05:24 PM	#7
RobRed ID10T Specialist 90 Rep 269 Posts Drives: F90 \| F97 Join Date: Aug 2014 Location: Nor Cal iTrader: (1) Garage List 2019 BMW M5 (f90) b ... [9.92] 2021 (F97) BMW X3mc [10.00] 2017 Toyota Land Cr ... [9.50] 2000 Toyota Land Cr ... [0.00]	there have been examples that don't adhere to the stated electronic limiter at 155/163 the car is capable of 190mph when the limiter is off. i have friend who is s feature editor at a major car mag and they regularly see examples of this. the 155 limit was a friendly limit set by manufacturers. i wouldn't be too concerned over this and it doesn't mean the car for sure has a tune.
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