offset on wheels...piccies to show

[sootyscottie]

I have fitted some new wheels to my car.

I had on 16" wheels with 205/55 tyres with 50 offset.



Bought some new wheels, which are 18" 235x40 43 offset.
Now i knew they would pertrude a little bit more, 7mm to be precise.

however, now they are fitted, i think they are to far out, and unless the wheel arcs inwards when it moves closer to the wheel arc, i am not sure if i am going to be able to lower the car much.



i will get a better picture tomorrow to show the exact thing. The rears are ok , it is just the front.

As you can see from the picture though, it does appear to be a lot further out that 7mm.

Where have i gone wrong? Some one fill me in on why i am being so dumb!!

I thought perhaps it was down to the wheel being a 7.5 with 235 tyres fitted, so the tyre is hanging over a bit more, but then my old wheels/tyres did that.

confused

[NickPicks]

The offset is the distance form the mounting face to the centreline of the wheel, so a 43 offset compared to a 50 will move the whole wheel out by 7mm. In addition to this, you've added 30mm of width to the tyre, so the outer edge is 15mm further out from the wheel centreline. Add these together and your tyre edge is 22mm nearer the wheelarch than before.

The supplier should have been able to check whether the wheel and tyre combination should fit your car.

For everything you could ever want to know about tyres, visit: tyre_bible

[BDT]

What we need to know is the width of the new rims, and not just the tires on them.

I'm guessing your old rims are 7in wide, and the new ones are 8.5 inches wide, hence why you now have so much rubber over hanging the arch.

When you bought your rims, it probably said 18in x 8.5 wheels, but often when you buy a tire/wheel combo, all that is quoted is the size of the rubber 235/40/18

You have only allowed for the difference in offset and have not looked at the difference in wheel width.

Personally, i always stick to the manufacturers offset of the car, as i have seen many cars handling ruined by offset changes as little as 5mm.

Unless you can return the wheels, I'm not sure how your going to get away with this, especially if the tires rub, unless 225's or 215 might clear your arches, unless you have your arches rolled ?

[sootyscottie]

ok here is a few more piccies.







Now i know where i have gone wrong.

I fatefully made the assumption that as the a3 s line has 18" 225 wheels on, it meant that these would fit. Am i correct in saying then that the s line alloys will be a differant offset to accomodate for the extra wheel width? Does any one know what the offset is on these?



Ohh, and does anybody want to buy a nice set of genuine A4 dtm wheels in 18"

[euroslap]

Only thing I could suggest is dropping your tyre width to say a 205 giving you a bit of tyre stretch, you should be able to drop it a bit more then.

[sootyscottie]

I think i am going to bite the bullet and get some new wheels.

Tbh, i dont really like the look of tyre stretch....... And the missus will h8 it i know for a fact.

It is a shame really, cos these are really nice wheels..

Looks like i am on the hunt for wheels again now. Took me blinkin ages to decide on and find these ones.

BAH!!!

[sootyscottie]

Right i am getting a bit miffed now.
Been having a browse on the web for wheels.
Looking at replica's etc.

When they ask you what car you have etc, they always seem to recommend 45 offset on 18" 225 wheels. Surely these are going to give me the same friggin problem.

I am starting to get peaved now. Nobody seems to do a offset greater than 45......

If anybody can find me some nice multispoke wheels, that are fairly good price, and will fit my car, and let me lower it with out the front wheel rubbing the outer arc,please let me know.

I have now given up and am going to go play mario cart fora bit.

BAH!

[MalcQV]

Mario cart is the only Wii game I have played for more than 10 mins!

Wheel offsets, widths are a minefield. I just went for it on my Passat (17" RS6 replicas on 225's) and they look great (to me). The car would look better lower, but the ride is just about right as it is.

[NickPicks]

I'd recommend elite in Rainham, Essex http://www.elitedirect.com

They were the most helpful people I found when I had exactly the same problem many years ago with my Lancia Delta. (My local wheel shop had supplied me with 37 ET wheels when the standard ones are 45 - This caused the rear tyres to rub the arches going round corners.)

A couple of things you might be able to do:

= You could have the arches rolled - this folds the inner lip of the arch up inside itself, which should give an extra 5mm of clearance. I'm not sure whether this will affect the paint around the lip of the arch. A body shop should be able to advise about this.

= It could be possible to have the mounting face of the wheel machined down to alter your offset. This is a specialist job, and the strength of the wheel needs to be considered (Making it thinner will make it weaker, but this may be how the wheel manufacturer makes different offsets - makes one casting, then machines the face differently). I'd suggest you visit a wheel specialist to ask their advice.

One final point:

When you bought the wheel / tyre combination, did you specify what car it was to fit? If you did, and the supplier have supplied you something which doesn't fit, then you should take the whole lot back to them and explain why it isn't "Fit for purpose". This is a term from the sale of goods act which specifies that goods must be fit for the specified purpose. If you've told them what car it's for, and they don't fit, then they really should be obliged to give you a refund.

This is what I did with my Lancia wheels, and they gave me a full refund (after investigatign the possibility of rolling the arches), which I then went and spent it at elite on some wheels which did fit.