I'm really really terrible at explaining things but I think we need a FAQ on offsets as its a common asked question.

If your good at writing articles and know what your talking about if you could please write up a post explaining offsets it would save the same question being asked over and over.

If you create the post as you would normally (in this section) then PM me I will make it a sticky so you wisdom can be passed on to the masses.

Cheers,

Kam.

Ok here are the basics!

Offset is the distance from the wheel center to its mounting surface.

The left picture show you a negative offset - which is see very rarely on alloys.

The middle picture should you an offset (ET) of 0 - its right in the centre of the width of the wheel

The right picture shows you a positive offset say ET35 (VAG std on some alloys) which means the mounting hub is 35mm closer to the face of the wheel than the Zero offset!

The higher the number the closer under the arches the wheels are going to sit - for example Vauxhall offset is ET49 - 14mm closer into the arches than std wheels - doesnt sound like much, but it can mean the difference of the wheels catching the brakes or the suspension.

The lower the offset the further out of the arches the wheels sit - for example ATS Classics ET20 which means that they stick out 15mm further the the std offset.

Cheers - thats reet helpful.

Is this the reason why some of the same model of wheels can be seen with different dish depths? Or is that a different thing altogether?

This may help you :) Did me,

http://www.1010tires.com/WheelOffsetCalculator.asp

Even better - you lot are dudes!

When it asks for offset does it mean the ET number? Sorry for all the questions, i gotta start somewhere!

I'm assuming for now the standard ones on my Polo will be 6 x et35 then?

this may also help you.

i love this help site

wheels explained

theres alot to read but most of it is very helpful

Even better - you lot are dudes!

When it asks for offset does it mean the ET number? Sorry for all the questions, i gotta start somewhere!

I'm assuming for now the standard ones on my Polo will be 6 x et35 then?

yes, the 'ET' number is the offset

Cheers mate, I'm beginning to understand it i think!

So would a 7" x 14" Brock B2 for example, with an offset of et25 have a deeper dish than that of an et35 offset?

I find that this helped mee :-D

http://www.carlsalter.com/wheel_fitments.html

http://www.bikerlifestyle.co.uk/tech/pcd/wheelstyres.htm

Edited 26 June, 200719 yr by Buzz

Cheers mate, I'm beginning to understand it i think!

So would a 7" x 14" Brock B2 for example, with an offset of et25 have a deeper dish than that of an et35 offset?

hey.

i dont know whether there would be a difference in dish depths between the et25 and et35, but the wheels with the et25 (offset of 25) will stick out more towards the outer wheel arches compared to the wheels with the offset of 35, i.e. away from the suspension.

remember, the lower the offset figure, the more the wheels will stick out of the car.

Edited 27 June, 200719 yr by davelondon

Cheers mate, I'm beginning to understand it i think!

So would a 7" x 14" Brock B2 for example, with an offset of et25 have a deeper dish than that of an et35 offset?

I think the answer to this question is possibly. Not definitive I know but if both a brock B2 with ET25 and ET35 were the same total width, used the same amount of material i.e. thickness for the centre mounting part of the wheel then you would effectively have 10mm more dish on ET25 wheel as the outside face of the wheel mounts 10mm further inside the wheel. (If that makes sense?!??!)

Pretty sure thats right.

Right. as i thought.

I was was just wondering why you tend to see the same wheels on different cars, with the only difference being one set is far dishier than the other. I dont want to order some nice dishy wheels only to get them and find they're nowhere near as deep as id thought...

I totally understand the et offsets now anyway!

Its simple once you see the basic principal. Take the width of the wheel,and half it. That is the centre line. The offset is measured from the centre line,the direction of which is from the back of the wheel,so added 'et' offset takes the hub face further to the front of the wheel,making the back deeper (more brake clearance). And minus offset brings the hub face the other way,so the outside of the wheel can look deeper,depending on the design.

So if you have a 7" wide wheel,at et38,thats 3.5" plus 38mm. So the hub face is 121mm in from the inside seat of the rear outer flange. Remember,the et is from the centre of the wheel,so whilst et38 of a 5" rim has a 3mm deeper back than an et35 of a 5" rim,its actually about 6mm shallower than an et32 of a 6" rim due to the 6" rim's extra half inch either side of the centre. So its no good saying 'I've got a wheel with an et42,will it fit my Polo?" without knowing the width of the wheel. Because whilst that offset of a 5" rim will fit okay,a 7" rim will rub the suspension - as the extra inch on the inside makes it the same as an et65 of a 5" rim on the inside half of the wheel.

So,you've got your wheel width (measured by the tyre seat,inside of the outer flange),centre line,and then the plus/minus offset of that centre line.

does anyone no the offset on 13 x 8 ally cat rallye specials. would it say on the wheel?

So MikeyMK... going by your theory, a rim that is 7" with an et30 should have a bigger dish (kerb side) than it having an et35...? Am I right or have I got that round the wrong way?? I'm rather confused here

So its no good saying 'I've got a wheel with an et42,will it fit my Polo?" without knowing the width of the wheel. Because whilst that offset of a 5" rim will fit okay,a 7" rim will rub the suspension - as the extra inch on the inside makes it the same as an et65 of a 5" rim on the inside half of the wheel.

but you can fit a spacer to your hub to take the wheel away from the suspension, taking the wheel towards the arch so make sure you lower at the right mm. Choose your wheels (size) before lowering, good luck

meh..

the lower the ET the bigger the dish

Cheers mate, I'm beginning to understand it i think!

So would a 7" x 14" Brock B2 for example, with an offset of et25 have a deeper dish than that of an et35 offset?

not neccesarily a deeper dish but they would stick out further

does that make sense

does anyone no the offset on 13 x 8 ally cat rallye specials. would it say on the wheel?

yes it should most wheels have it stamped or moulded into the rear of one of the spokes

hey guys, i know u put on links about offsets but it baffles me. anyway, thought id ask u experts this, I've just bought some mim alloys, set at 7x15'' et 13!!. now from all the numbers u lot are talkin bout they're like et 35 et 35 et 42 etc, am i way off in thinkin mine will fit and not rub? my gt is lowered 40mm all round and i presumes the tyres ill get for the new rims will be 195/45/r15, unless i can get 195/40/r15? cheers guys look forward to hearing you are replies.

FITMENT: 6.5J X 15H2

what does that mean?

FITMENT: 6.5J X 15H2

what does that mean?

6.5 (inches) is how wide the wheel is , 15 (inches) is the diameter of the wheel

thanks!

how do you determine what tyre to fit on a wheel?

for example if my tyre is 13 but width of new alloy is diff could i still stick the same tyres on or would it ahve to be diff tyres?

are the mathces set in stone

Edited 25 April, 200818 yr by polpolo

thanks!

how do you determine what tyre to fit on a wheel?

for example if my tyre is 13 but width of new alloy is diff could i still stick the same tyres on or would it ahve to be diff tyres?

are the mathces set in stone

not sure i get what you mean, if the tyre is lets say 195/50/13, 13 being the diameter the alloy would have to be 13 in diameter aswell.

(the diameters have to be same for both tyre and wheel). Hope thats what you mean. :-D

not sure i get what you mean, if the tyre is lets say 195/50/13, 13 being the diameter the alloy would have to be 13 in diameter aswell.

(the diameters have to be same for both tyre and wheel). Hope thats what you mean. :-D

kind of lol

what i mean is - the diameters have to be the same - fair enough

what about the rest? does the rest not matter? i.e. i have tyres which are 155/70/13 how do i know what alloys they will fit?

cheers!! :-D