Ok, as there is a constant flow of people asking questions about wheels I thought I would put this thread together to try and answer most of the questions in one go. Maybe a mod can make this a sticky?
The first link explains wheel measurements clearly, including PCD and offset:
LINK 1
Standard Saxo fitment is 4x108 et15 (ET is another way of writing offset)
If you looking at fitting different wheels, for a direct fit they also need to be 4x108 et15.
Different offset
Offset can be altered with the use of spacers.
E.g. 20mm spacer will minus 20mm from the offset.
A common fitment is 4x108 et35 (ford). These will fit with a 20mm spacer as explained above.
If you are using spacers bigger than 5mm, generally you will need longer wheel bolts although if you are using spacers which are 20mm or larger, I would advise using spacer that use a different set of bolts to bolt to the hub first then the wheel bolts to the spacer using the original wheel bolts. These are much safer than using longer bolts.
Different PCD
If you want to fit wheel with a different stud pattern (PCD) then the easiest way is hub adapters. You can pick these up for about £100 for a set of 4.
Probably the most common use for hub adapters is from 4x108 (Saxo) to 4x100 (VW and Renault)
Ebay is usually the cheapest for hub adapters but shop around.
Wide wheels
Want to fit wider wheels?
The next link will calculate the required offset for you.
LINK 2
How it works:
Enter the current wheel specs. So for a saxo that is width of 7 inches and offset of 15
Then enter the width of the wheel you want to fit in the 'new wheel specs' box.
E.g. 8 inches
Then hit calculate.
The site will then tell you the inner clearance and outer position of the new wheel.
Now you need to go back and alter the offset of the new wheel until the inner clearance says THE SAME
E.g. if the results say:
Inner clearance: 30mm less
You need to minus 30mm from the new wheels offset.
This will mean that the extra width of the wheel will be on the outside of the wheel. This is how it needs to be so that the wheels don’t rub or catch on anything in the wheel arch.
it is possible to fit 8j on the front and 9j on the rear of a saxo.
Stretched tyres
If you are thinking about fitting wider wheels then you may also be thinking about having stretched tyres.
The following link has lots of pictures of different size tyres on different width wheels so you can choose which size you want on your wheels.
LINK 3
A little bit of info about stretch tyres:
Most importantly, you can’t drive you car hard on stretched tyres safely. So if you like nailing it down country roads. Don’t even think about stretched tyres. They will make the handling worse. If you want handling, fit the proper size tyre for that wheel.
As far as I am aware the law states that the tread of the tyre has to be under the wheel arch. In other words this means that the tyre wall can be outside the wheel arch. This is why most people run stretched tyres, so that they can fit wide wheel (wider than the wheel arch) and still have the tyre tread under the arch making the car legal to drive on UK roads.
Although if you get a ticket for your wheels protruding from your arches, don’t come back to me. If your in doubt check with your local police first. Even though most of them don’t know anyway.
Larger wheels
If you’re looking to fit larger wheels i.e. 16's, 17's etc this can also be done.
16's will fit without any arch modifications when fitted with 40 profile tyres
17's will need arch work done. It is easiest if you run 35 profile tyres for 17's.
The standard tyre size for 15 inch wheels is 195/45/15
The following link will calculate the overall diameter of the tyre.
LINK 4
This is what’s important when fitting bigger wheels. Not the actual size of the wheel itself although this obviously has an effect on the overall diameter to an extent. The diameter will also effect your ride height. Bigger, the car will go up. Smaller, the car will go down.
I think I have covered everything. If you can see I have missed something. Please post it up and I will add it in.
Going to ask a question about wheels or tyres? READ THIS FIRST
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