Slave2school
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If you have vagdashcom you can. I've had no joy trying to change my vss code to the other one listed on the vag-com webpage.
__. I recently put 205/65R15's (Michelin "Energie") on my '03 Wagon (some A4's have 15" wheels; I'm guessing the OP's A5 has 16's). The speedo now reads *perfectly* -- less than 1 second variation over 5 miles at 60 MPH indicated. Of course, now I have to do the math to get an accurate odo.Ernie Rogers said:(snip) Just doing the math, changing to the 205/65R16 tires should make your speedometer right on, BUT (snip)
You may be surprised on this one. Stock VW alum wheels are fairly heavy, I would not be surprised if the 16's are heavier. If you want light you may want to go with the 15" alum rims from the TDi GLS (also check mk3 vr-6 which came with 15" 5x100 alum rims).WVU TDI said:I've got a similar question; my '01 TDI came with the 15" steelies and 195-65/15s, I've found a set of OEM ALuminum Beetle 16s with 205 Kumho SPTs.
Will I see much of a difference either way here? I figure the wheels are gonna be quite a bit lighter, but the tires are maybe a little heavier (wider, through shorter...) and probably stickier than the Bridgestone G009s that are on it.
Anyway, overall thoughts?
Or if they buy some really high end alloy rims which are really big moneypearse said:You may be surprised on this one. Stock VW alum wheels are fairly heavy, .
I believe so.HopefulFred said:Is VAGdashCOM the only way to edit your speedometer? .
06_Jetta_TDI said:I own an 06 Jetta TDI. I noticed that my Speedometer is 3 or 4 Miles off what it should be IE: If I'm going down the road 75 I'm really going just a little over 70. This is a fact that I am guessing many of you are familiar with. (VW even admited they knew about it)
When I went from 195-65-15 Winter tires to 205-55-16 Summer, I noticed, what seemed to be a dramatic drop in fuel mileage. I had expected it to drop, but not that much. I had checked the difference on a tire size calculator I had located on the web (link below), but it wasn't anything significant. It wasn't until I noticed the mileage difference on my odometer that it got my attention. I checked mileage between two known points with the different size tires, and for 50 miles, the odometer was reading about 3% lower than with the 16" than the 15". I then added 3% to my mileage total and the fuel usage, while still higher than with the 15" tires, was what I had expected. I hope this helps a little bit.06_Jetta_TDI said:Here is the question....
I have 205/55/16's on the TDI. Can anyone tell me if it would be a good or bad idea to go to a 205/65/16? This makes about a 3.9 mile an hour difference according to this tire size web site which would make me closer to correct on the speedometer and odometer, and would this not also show better fuel economy? (less revolutions per mile)
http://www.miata.net/garage/tirecalc.html
I have called a few places (including VW) and they said the only thing they can think of that would come into play would be the ABS.
Any thoughts?
Your contact patch (tire to road) is now larger and therefore the rolling resistance has increased. That would account for loss of mileage.Uncle said:When I went from 195-65-15 Winter tires to 205-55-16 Summer, I noticed, what seemed to be a dramatic drop in fuel mileage. I had expected it to drop, but not that much. I had checked the difference on a tire size calculator I had located on the web (link below), but it wasn't anything significant. It wasn't until I noticed the mileage difference on my odometer that it got my attention. I checked mileage between two known points with the different size tires, and for 50 miles, the odometer was reading about 3% lower than with the 16" than the 15". I then added 3% to my mileage total and the fuel usage, while still higher than with the 15" tires, was what I had expected. I hope this helps a little bit.
http://neons.org/tire/
__. OK, now I gotcha! Yes, your thinking is correct and so is your math -- except I've never seen any tires match the "theoretical" rolling radius exactly. Those radius numbers are useful as comparison and for relative comparisons but you're going to have to measure your distance (for the odo) and time (for the speedo) as the tires actually work on your car. But you'll probably see numbers that pretty much reflect your calculations - but you can't depend on the calculations alone.vwxyzero said:Mr. GW,
I understand everything you said, maybe I wasn't clear enough.
Quick note(s):
_I own and drive two 96' B4's, one is a Sedan the other a Varient.
_I understand that both the spedo and odo are affecteded by up-sizing tires.
_I understand that the B4 spedo reads slightly under the speed I am actually traveling, but the odo is spot on.
_The Stock tires on a B4 are 195/60/14.
_I just up-sized to 195/65/14 which are taller and affect both my spedo and odo.
I'm just trying to figure out if the formula I used (above) is an accurate way of calculating actual miles driven.
Ernie Rogers said:Hi,
...Just doing the math, changing to the 205/65R16 tires should make your speedometer right on, BUT
I'm a little concerned about making mistakes. If you get the much bigger tires and go too far, you may be uncomfortable with the speedo reading TOO LOW. If the bigger tires interfere with the car structure, you'll have new tires you can't use.
Ernie Rogers
Did you go with the 205/60R16's , i want to do the same and was worried about these same issues and clearances, any thoughts?06_Jetta_TDI said:Well this kinda answered my question I guess. I'm not hearing anyone concerned with any ABS issues etc. I am a little concerned with the "rolling resistance and gear ratio" backfiring on me.
I know for a fact that in my case...my odometer IS off (I wonder if something happened with the newer Diesels? Why is my odometer off and yours is not?). I've done this several times....watching the mile markers get farther and farther away when I should be right on it....and my last trip to work should be 56.6 miles away and my odometer showed I traveled 57.4 miles.
I'm just having a hard time figuring out if I would make that big of a change from 205/55/16 to 205/65/16 if that would throw my odometer to far off in the other direction. Maybe I will go to a 205/60/16 for starters and see how that goes. I just want my speedometer/odometer to be more accurate than what it currently is. I have an F150 as a second vehicle and the odometer on it is dead on with the highway mile markers...
It looks like 205/65-15's are the largest diameter that has been tried. Has anyone put on anything taller than 25.49"(205/65-15) on an A4?mrGutWrench said:__. I recently put 205/65R15's (Michelin "Energie") on my '03 Wagon (some A4's have 15" wheels; I'm guessing the OP's A5 has 16's). The speedo now reads *perfectly* -- less than 1 second variation over 5 miles at 60 MPH indicated. Of course, now I have to do the math to get an accurate odo.
__. But I don't really care about the speedo - what's been the sweetest is that it's completely transformed the ride and handling of the car (not to mention the MPG). On the other hand, anything would be better than the cheepo Jap tires on it before.
Any change you make that makes the speedometer more accurate will have an adverse effect on odometer accuracy.thatvwguy said:For the sake of better ride and a more accurate spedometer I have been thinking about going to a taller tire.
True, but I have never got a ticket for tracking my mileage wrong. Speeding is another issue. It is much more important to me to have an accurate speedometerTornadoRed said:Any change you make that makes the speedometer more accurate will have an adverse effect on odometer accuracy.
My speedometer is off by 3 mph. My odometer is accurate to less than 0.1% (one mile per thousand). I will not be changing tire sizes.
__. I'm OK with making odometer calculation adjustments. I just don't like how the oversided tires work on my car -- I wish that I had stuck with stock.TornadoRed said:Any change you make that makes the speedometer more accurate will have an adverse effect on odometer accuracy.
My speedometer is off by 3 mph. My odometer is accurate to less than 0.1% (one mile per thousand). I will not be changing tire sizes.
Have you made the jump to a different sized tire yet? Just curious because I seem to have the same issue you do on my '06 Jetta. My speedometer reads 5mph faster than actual speed, and my odometer ticks off the miles too fast as well.06_Jetta_TDI said:I own an 06 Jetta TDI. I noticed that my Speedometer is 3 or 4 Miles off what it should be IE: If I'm going down the road 75 I'm really going just a little over 70. This is a fact that I am guessing many of you are familiar with. (VW even admited they knew about it)
Here is the question....
I have 205/55/16's on the TDI. Can anyone tell me if it would be a good or bad idea to go to a 205/65/16? This makes about a 3.9 mile an hour difference according to this tire size web site which would make me closer to correct on the speedometer and odometer, and would this not also show better fuel economy? (less revolutions per mile)
http://www.miata.net/garage/tirecalc.html
I have called a few places (including VW) and they said the only thing they can think of that would come into play would be the ABS.
Any thoughts?
When my speedometer shows 75 mph, I know that my true speed is 72 mph. If it shows 45 mph, the true speed is 42 mph. I never have to worry about getting a ticket because I don't know my true speed.thatvwguy said:True, but I have never got a ticket for tracking my mileage wrong. Speeding is another issue. It is much more important to me to have an accurate speedometer