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View Full Version : 16" to 17"s ???



Nick
04-10-2009, 09:59 AM
Hey Guys

Im looking at replacing the standard 16" Cleveland alloys on the Golf with a set of 17" Seattle (same as thosefitted as part of the sport pack)

Can anyone tell me if they're a direct swap...no further modification required other than putting the things on???

Also, if i fit the 17"s and the dinky soare ever has to be used will it cause any probs? Im guessing the spare is the same diameter as the wheels fitted to a car i.e. 16" spacesaver fitted to car with 16" wheels and 17" on one with 17's???

mikinoz
04-10-2009, 10:32 AM
Hi Nick,

They are a direct swap.

You should never run different diameter wheels on the front, so if you need to use the spare, stick it on the back until you get the tyre repaired. You put extra strain on the diff otherwise, small amount but can cause damage.

Nick
04-10-2009, 11:38 AM
Cheers

Thanks for the info mate.

I suspected they were a direct swap but didnt want to get caught out.

I guess it just means if i get a flat on the front then i have to swap a back one to the front then put spare on the rear. Prob makes sense andhow in an idea world not to put your spacesaver on the front unless at all unavoidable.

philthy
04-10-2009, 12:35 PM
Hey Guys

Im looking at replacing the standard 16" Cleveland alloys on the Golf with a set of 17" Seattle (same as thosefitted as part of the sport pack)

Can anyone tell me if they're a direct swap...no further modification required other than putting the things on???

Also, if i fit the 17"s and the dinky soare ever has to be used will it cause any probs? Im guessing the spare is the same diameter as the wheels fitted to a car i.e. 16" spacesaver fitted to car with 16" wheels and 17" on one with 17's???

I would think you should have the same rolling diameter with either 16's or 17's, ie the 17's will be fitted with lower profile tyres.. shouldn't be a drama to use the spare.

tofo17
04-10-2009, 01:59 PM
Won't be a drama at all. I just replaced my Clevelands with 17" Classixs (literally yesterday). As long as you run 225/45 you will have the same rolling diameter.

logger
04-10-2009, 03:15 PM
If on the other hand one was trying to put 16" on a 17" Sports pack car (which is unlikely I know) you would have to recode the ABS controller for the Tyre Press Warning sytem to work properly. It needs to know wheel rim size in inches. So it is not always a straight forward swap with same rolling diameter.

I agree the spare should be the same diameter and should be Ok on the front to get out of a bind.

pologti18t
04-10-2009, 10:34 PM
If on the other hand one was trying to put 16" on a 17" Sports pack car (which is unlikely I know) you would have to recode the ABS controller for the Tyre Press Warning sytem to work properly. It needs to know wheel rim size in inches. So it is not always a straight forward swap with same rolling diameter.

.

Why does the ABS controller need to know the rolling diameter of the wheels at all... You reset the system every time you set your tyre pressures... it then monitors the ABS signals overtime to see if there is any change between the 2 pairs of tyres. If there is a warning appears to prompt the driver to check the tyres. Simple as that.

logger
05-10-2009, 06:52 AM
Why does the ABS controller need to know the rolling diameter of the wheels at all... You reset the system every time you set your tyre pressures... it then monitors the ABS signals overtime to see if there is any change between the 2 pairs of tyres. If there is a warning appears to prompt the driver to check the tyres. Simple as that.
Wish it was as simple as that but it is not. I do not know why - but it does.

Only thing I can think of, is for a given pressure change between different sized wheels (say a 10 lb drop) the resulting wheel speed change will be different. So 2 cars side by side one with 16" the other 17". Both driving @ 100kph and both lose 10psi in a single tyre @ the same time. The wheel diameters will now be slightly different as the smaller wheel will have lost more air. Therefore it will be spinning faster and the TPWS needs to know this so it can set the appropriate thresholds. You can read more about it here http://forums.fourtitude.com/zerothread?cmd=print&id=2484840

"First of all my car is 2005 A3 Sportback DSG, 2.0 TDI (BKD)

Address 03: ABS Brakes
Part No: 1K0 907 379 K
Component: ESP FRONT MK60 0104
Coding: original:0023174 new (with TPS routine activated):0006790
Shop #: WSC 06314
Adaptation
channel 1 stored value: 0 // Field1: Tire Pressure // Field2:15 inch // Field3: N/A // Field4: N/A
channel 9 stored value: 0 // Field1: Brake assist. // Field2: center // Field3: N/A // Field4: N/A
channel 10, and channel 90 required a security code


I followed the recode procedure of my ABS controller and the values from MB 31 starts to increment as expected from the learning procedure.
I have to change the adaptation channel 1 from 0 (15 inch) to 1 (16 inch).
After 100Km the values from MB031:
#1 5853
#2 5000
#3 5000"

roy
05-10-2009, 08:14 AM
different wheel size cause different caculation on speed which affects ABS, speedo, etc.
if the tyres size is the same just change the alloy which means the tyre will be thinner...then don't worry... wheel size is the same...

logger
05-10-2009, 09:03 AM
I think we can all grasp what you are trying to say, but to be more correct... different rolling diameters (not wheel sizes) cause different calculation on speed which affects ABS, speedo, etc.

However for some reason that is not immediately obvious, the ABS controller has input fields for wheel sizes, when rolling diameter through all three stock tyre sizes remains constant. My uneducated guess is that the the TPWs will still work without the correct wheel size coded, but perhaps not as well.
I can see 24 differences between the ABS controller coding in the 16" standard and 17" sports pack TSI. For a Different suspension setup and TPWs thats a lot of differences and they will all be there for a reason.