Looking to go from 18" to 19" and switch to non runflats at same time
Explain offsets to me please
- Thread starter jamesgarbett
- Start date
The offset figure defines where the wheel sits on the hub in respect of how far it sits in or out in regards to the boby of the car.
The lower the offset figure compared to the original the further the wheel protrudes out from the car and vice versa.
The width of the wheel will also have some bearing as to where the wheel sits so it's best to use THE GOOD OLD OFFSET CALCULATOR to get some idea.
I have 19s on my 3.0 8.5 fronts and 9.5 rears with an offset of 35 all round and they fit perfectly.
The lower the offset figure compared to the original the further the wheel protrudes out from the car and vice versa.
The width of the wheel will also have some bearing as to where the wheel sits so it's best to use THE GOOD OLD OFFSET CALCULATOR to get some idea.
I have 19s on my 3.0 8.5 fronts and 9.5 rears with an offset of 35 all round and they fit perfectly.
oke:Stolen from my old Scirocco forum:
ET is measured fromt he centre line of the wheel (i thought) like so;
And the closer to the centre you go, the more the wheel pokes out. So an offset of 0 will poke out 38mm more than a 38mm ET wheel.
ET is measured fromt he centre line of the wheel (i thought) like so;
And the closer to the centre you go, the more the wheel pokes out. So an offset of 0 will poke out 38mm more than a 38mm ET wheel.
Interesting... on my e89 I have the 19" 296 wheels that are notorious for cracking. No problems at the moment, but if I keep this car I'm strongly considering 18" wheels with normal, non RFT tyres to improve the comfort. My offsets are ET29 front and ET40 rear.
Most of the wheels I like are offset ET35. Which would mean the fronts protrude more than stock by 6mm? ..and rears go in by 5mm?
Most of the wheels I like are offset ET35. Which would mean the fronts protrude more than stock by 6mm? ..and rears go in by 5mm?
If you have a staggered setup now (which you must have if teh offsets are different, right ?), would you not try to retain a staggered setup rather than go the same all round, even with 18" instead of 19" ?
I like this thread by the way - it has totally demystified this subject for me. If only I knew the offsets of my wheels...
Lower offset, stick out more, higher, stick out less, so the other way round I think Maniac ? And depends on the wheel width as said above...
I like this thread by the way - it has totally demystified this subject for me. If only I knew the offsets of my wheels...
Lower offset, stick out more, higher, stick out less, so the other way round I think Maniac ? And depends on the wheel width as said above...
Here is an offset calculator than will allow you to actually see the effect of different offsets between 2 wheels...
http://www.rimsntires.com/specs.jsp
http://www.rimsntires.com/specs.jsp
Maniac said:
No matey, your original fronts are 29 offset which is lower than the new 35 offset so the originals would protrude more. The original rears are 40 offset which is higher than the new 35 so the new ones would protrude more.
Remember the wheel with the lower offset whether it's a new one or old one protrudes more providing they are both the same width.
Dav the wheel nut said:
Right... :rofl: I think I'm getting this... so other way up... Fronts will go in slightly, backs will protrude slightly... Then I guess its all about checking for arch interference on the backs and possibly suspension fouling at the front... But as they're just a few mm... The other thing I'd not considered was the rolling circumference which is very handily demonstrated by that online tool thing.
The differences are really so small you shouldn't have any issues.
If you go for the 19 inch wheels don't forget they are wider front and rear and the figures will be different.
As for the rolling radius, that is tyre dependent, so get the wheels first and calculate that afterwards :wink:
If you go for the 19 inch wheels don't forget they are wider front and rear and the figures will be different.
As for the rolling radius, that is tyre dependent, so get the wheels first and calculate that afterwards :wink:
Hi guys, this has also confused me. I've got a staggered set of CSL reps from a previous car, hoping to fit them to the z. The wheels are 18, 9.5 45 which I ran at the back and 18 8.5 40s which I ran up front. I had to get my guards rolled for the back as when ppl sat in the back and went over bumps, I could hear the tyres hitting the guards.
I have a feeling, these wheels may not fit the Z but a confirmation would be great. Thanks in advance
I have a feeling, these wheels may not fit the Z but a confirmation would be great. Thanks in advance
wmj73 said:Hi guys, this has also confused me. I've got a staggered set of CSL reps from a previous car, hoping to fit them to the z. The wheels are 18, 9.5 45 which I ran at the back and 18 8.5 40s which I ran up front. I had to get my guards rolled for the back as when ppl sat in the back and went over bumps, I could hear the tyres hitting the guards.
I have a feeling, these wheels may not fit the Z but a confirmation would be great. Thanks in advance
I'm assuming the offset figure is 45 rear and 40 front in which case they will fit ok if they came off a similar series BMW
Dav the wheel nut said:wmj73 said:Hi guys, this has also confused me. I've got a staggered set of CSL reps from a previous car, hoping to fit them to the z. The wheels are 18, 9.5 45 which I ran at the back and 18 8.5 40s which I ran up front. I had to get my guards rolled for the back as when ppl sat in the back and went over bumps, I could hear the tyres hitting the guards.
I have a feeling, these wheels may not fit the Z but a confirmation would be great. Thanks in advance
I'm assuming the offset figure is 45 rear and 40 front in which case they will fit ok if they came off a similar series BMW
Thanks for the reply, yes you are correct and I had them on a 1 series coupe
