Speedometer Calibration with OBDEleven?

[Shane_Anigans]

Searched the OBDeleven thread (and some other places), but I haven't found the answer I'm looking for, so apologies if this has been covered elsewhere.

Backstory: bought used wheels/tires for winter, they're sized 215/55/17, 4.8% larger diameter than stock (26.3" vs 25.1"). I know that this will (theoretically) make my indicated speed lower than my actual speed, but that most cars speedometers read lower than actual with the standard tire size, to prevent idiots like me from blaming the car company for their speeding tickets.

Now, I bought the wheels/tires from a guy who'd had his 2013 Passat TDI bought back, and he told me when I purchased them that his car has a setting in the MIB (car>wheels>winter) that allowed him to adjust the speedometer by up to 5% to compensate for taller winter tires. However, in my 2017 GTI Sport, the only option I have in that menu is to set a speed warning. Others have told me that their older GTIs had the same feature, so I'm wondering if this is something that can be enabled using OBDeleven, and if so, how?

(Oh and in case anyone was wondering, yes, 17" wheels from an old Audi S4 will clear the PP brakes, though with bare millimeters of space between the caliper and the wheel weights. Also, the 1" taller tires do not rub.)

 

[nype]

If I recall, there is a tire size setting somewhere. Read about it a while back on one of the vcds threads. I’d have to do some searching to find it again.

 

[absoluteczech]

There’s a winter tire setting. You can do it on the mfd via steering wheel

 

[Shane_Anigans]

There’s a winter tire setting. You can do it on the mfd via steering wheel

I just checked the manual again, and there isn't one. I suspect it was removed for the 2017 model year, for whatever reason.

 

[MonkeyMD]

Did some research and per another forum, this option was removed in the mk7. If I find the link I'll post.

 

[nype]

http://www.golfmk7.com/forums/showthread.php?t=2491&page=63

See post 1059

I didn’t read further along in the thread but this is what I was referring to earlier.

From member “Sportwagen SEL”

—

I finally found a way to calibrate our speedo for those of us running different size tires/wheels!

Go to 17 dashboard
Long coding (the list mode not 0 and 1s)
Wheel Circ

Here you'll see version 1-8. My car was set on version 3 which match the stock 225/40 tires. I set it to version 1 as I have larger diameter 245/40 tires and now my speedo is just about right.

—

 

[Shane_Anigans]

http://www.golfmk7.com/forums/showthread.php?t=2491&page=63

See post 1059

I didn’t read further along in the thread but this is what I was referring to earlier.

From member “Sportwagen SEL”

—

I finally found a way to calibrate our speedo for those of us running different size tires/wheels!

Go to 17 dashboard
Long coding (the list mode not 0 and 1s)
Wheel Circ

Here you'll see version 1-8. My car was set on version 3 which match the stock 225/40 tires. I set it to version 1 as I have larger diameter 245/40 tires and now my speedo is just about right.

—

That's what I was looking for, sort of. It would be nice to know what sizes the settings correspond to, but it's a good start. Thanks!

EDIT: Investigated further, found this thread, which led me to this doc.

So, based on the numbers from this helpful tire size calculator, I'm going from 514 revs/km to 491, so setting 4 is the best possible option. Based on the table, the best setting for the factory tire size at 514 r/km is #2, (513), rather than #3. This makes sense, as we know that all car manufacturers set their speedometers to higher than actual speed, and German companies seem to have a greater deviation than most.

I started off wondering if this was going to be a stupid question thread, and it turns out there's something useful for everyone, even those using the standard tire size.

 

[MonkeyMD]

Wow. Didn't think it was possible with our cars. Testing tomorrow.

 

[Gray_Panther]

Let us know!

 

[Shane_Anigans]

Wow. Didn't think it was possible with our cars. Testing tomorrow.

Hopefully it is. The info I've gathered is clearly not from any MK7 owners, but I'm hoping its the sort of thing that the engineers don't feed the need to mess around with between varying generations of cars. We'll soon find out.

 

[absoluteczech]

Did some research and per another forum, this option was removed in the mk7. If I find the link I'll post.

My 2016 has it

 

[MonkeyMD]

My 2016 has it

Yes. I stand corrected.
About a year ago, Did a lot of research and asked on obd11 forum and here. Never received a response and research showed not possible..

 

[MonkeyMD]

That's what I was looking for, sort of. It would be nice to know what sizes the settings correspond to, but it's a good start. Thanks!

EDIT: Investigated further, found this thread, which led me to this doc.

So, based on the numbers from this helpful tire size calculator, I'm going from 514 revs/km to 491, so setting 4 is the best possible option. Based on the table, the best setting for the factory tire size at 514 r/km is #2, (513), rather than #3. This makes sense, as we know that all car manufacturers set their speedometers to higher than actual speed, and German companies seem to have a greater deviation than most.

I started off wondering if this was going to be a stupid question thread, and it turns out there's something useful for everyone, even those using the standard tire size.

Great find!!
Already collected some obd data on gps vs speedo discrepancy at stock level. Just updated to setting 1, but based on your feedback, might go to 4 since I'm running same tire size and will get data on that and post on here

 

[The Fed]

I've found my speedo to be right on by comparing to radar speed reminders.

 

[odessa.filez]

does it adjust odo too?

any settings for smaller diameter than stock?