The Perfect Offset...

[David]

I was hoping to get it finally written in stone (one piece that is easily accessible to everybody), what the perfect offets (and widths) would be for alloys on all the different zeds.

I realise that there will be some varying opinion of what constitutes the perfect fit (i.e stretched tyre crew), but in this instance I mean the perfect offset to bring the outside edge of the alloy legally inline with the arches, without the use of spacers.

I believe all Z3 front axles/body are the same, so this should be an easy one for us to answer.
But there are 3 different rears on the Z3 - 'Pre-Facelift Narrow', 'Facelift Wide', and 'Z3M / 2.8 Pre-Facelift Wide'.

I've not a clue what the answers are, so if people could contribute their findings, I would be grateful!
(And, if you couldn't tell, my understanding of widths and offsets is extremely limited, so please correct me if I'm wrong thus far!)

TIA,
David

The Perfect Offset - Z3 Front Axle:

Width - 8J Offset - 33/34/35​

The Perfect Offset - Z3 Rear Axle:

• Pre-Facelift Narrow:

TBC​

• Facelift Wide:

Width - 8.5J Offset - 37​

• Z3M / 2.8 Pre-Facelift Wide:

Width - 10J Offset - 33​

 

[Ashbandicoot]

interested to know!

Ash

 

[Alin S]

I found a website which details track width and body width while trying to figure out if Z3M wheels will fit on 1.8 facelift (wide body). All the specs attached.

I think they are extremely useful while trying to figure wheel widths and offsets.

 

[Brian4]

I found a website which details track width and body width while trying to figure out if Z3M wheels will fit on 1.8 facelift (wide body). All the specs attached.

I think they are extremely useful while trying to figure wheel widths and offsets.

Hi Alin

Z3m rear wheels will only fit a Z3M as they have such a small offset (deep dish). The Z3M almost has the rear trailing arms from a 1.8/9 narrow body in the wide body car. The narrow body trailing arms are shorter than the widebody. and face lift.

I believe it is possible to fit the trailing arms and drive shafts from a 1.8/9 to a 2.8 but the drive shafts are smaller diameter.
Or you can fit the wide body rear wings and bumper to a narrow body and the fit the M wheels.

I have found this site good for comparing how wheels will fit.

http://www.willtheyfit.com/

 

[Alin S]

Hi Brian,

Thanks for the info. I know Z3M wheels can't be fitted to the narrow body (there's a post on bimmerforums I believe - it looks awful and illegal without stretching the tyres a fair bit). However my car is a widebody 1.8 and I haven't seen any examples of how it might fit. I've moved on from the idea of Z3M wheels on my car (1.8) - too much show and not much go.

I'll list fitments which I liked though:
1. Styling 158 8X17 ET34 on 6 zyl - could prob do with 10mm spacers on the rear

2. Styling 194 F: 8X17ET34 R:8X8.5 ET37 on 4 Zyl photo 1 , Styling 162 F: 8X17ET34 R:8X8.5 ET37 on 6 Zyl Photo 2,3

To stop my rambling, I think the lowest usable offset irrespective of model is around 35 on an 8J wheel for the fronts and a similar offset for 8.5 - 9J rears. I also believe that in order to complement that type of offset and width , a 30 mm drop in ride height is necessary.

As you can prob tell, I spend a lot of time thinking about wheels .

 

[Brian4]

I like my ACS which are 17 x 7.5 et 35 front and rear but 245 tyres on rear which protect the rim edges more. I think it is standard suspension not the sport.

 

[Alin S]

I really like your car Brian. The fitment on the front looks excellent. Do you have a photo to show how the rear wheel fills the arches?

 

[t-tony]

Hi Brian,

Thanks for the info. I know Z3M wheels can't be fitted to the narrow body (there's a post on bimmerforums I believe - it looks awful and illegal without stretching the tyres a fair bit). However my car is a widebody 1.8 and I haven't seen any examples of how it might fit. I've moved on from the idea of Z3M wheels on my car (1.8) - too much show and not much go.

View attachment 15353

I'll list fitments which I liked though:
1. Styling 158 8X17 ET34 on 6 zyl - could prob do with 10mm spacers on the rear
View attachment 15350

2. Styling 194 F: 8X17ET34 R:8X8.5 ET37 on 4 Zyl photo 1 , Styling 162 F: 8X17ET34 R:8X8.5 ET37 on 6 Zyl Photo 2,3
View attachment 15351
View attachment 15355 View attachment 15354


To stop my rambling, I think the lowest usable offset irrespective of model is around 35 on an 8J wheel for the fronts and a similar offset for 8.5 - 9J rears. I also believe that in order to complement that type of offset and width , a 30 mm drop in ride height is necessary.

As you can prob tell, I spend a lot of time thinking about wheels .

What makes you say that tyres exposed outside the wheel arches are illegal Alin ? Although it may be I doubt if police would pull you up for it, and there's nothing in the M.O.T. To fail a vehicle for it either. It's merely an advisory item. Personally I don't think it's a good idea, but also I hate seeing tyres stretched out the way some people have them, but the same applies.

Tony.

 

[Brian4]

Best I have got at the moment. Day after a day out so filthy blame @BMBabe

As you say with 8.5 on rear would be 12.5 mm further out so be right at edge but may foul the arch liner if lowered with full suspension travel.

 

[Alin S]

What makes you say that tyres exposed outside the wheel arches are illegal Alin ? Although it may be I doubt if police would pull you up for it, and there's nothing in the M.O.T. To fail a vehicle for it either. It's merely an advisory item. Personally I don't think it's a good idea, but also I hate seeing tyres stretched out the way some people have them, but the same applies.

Tony.

Hi Tony,

I think that if you have tread beyond the arches, it doesn't meet the legal requirements for spray suppression.

Alin.

 

[Alin S]

Best I have got at the moment. Day after a day out so filthy blame @BMBabe

As you say with 8.5 on rear would be 12.5 mm further out so be right at edge but may foul the arch liner if lowered with full suspension travel.

You're right, it is a possibility. I've seen Zeds with more extreme setups allegedly running without rubbing.

 

[zedonist]

The legality of Poke...

The motor vehicle regulations act of 1996 states in section 18 paragraph 2 subsection D that the front face of a wheel on the vertical plane may protrude from the wheel arch/mudguard a maximum of 30mm but the tyre tread must be covered

 

[Brian4]

The legality of Poke...

The motor vehicle regulations act of 1996 states in section 18 paragraph 2 subsection D that the front face of a wheel on the vertical plane may protrude from the wheel arch/mudguard a maximum of 30mm but the tyre tread must be covered

Hence the need for these, not good on a zed!!

 

[zedonist]

That's nice Brian is it yours?

 

[Brian4]

No stole it off tinternet. does look good though. My mate when 18 had a Cooper S, was great fun till he wrapped it round a tree in the New Forest. He walked away though.

 

[t-tony]

The legality of Poke...

The motor vehicle regulations act of 1996 states in section 18 paragraph 2 subsection D that the front face of a wheel on the vertical plane may protrude from the wheel arch/mudguard a maximum of 30mm but the tyre tread must be covered

That is as may be Rich, the point I'm making is most police wouldn't, a) know that or b) be bothered to stop you for that alone, they have bigger fish to fry. And as I pointed out, the law is an ass when I would have no option but to pass and advise this on a test!

Tony.

ps. Is this part of the reasoning behind stretching the tyres to absurdly over wide rims then?

 

[David]

Styling 162
Front:
17X8 ET34
Rear:
17X8.5 ET37 on a 6 Cylinder
View attachment 15355 View attachment 15354

Tried to tidy this up a little for you, but these wheels look great, as far as filling the arches goes. I think they look spot on for the Facelift!

 

[t-tony]

These may only muddy the waters a bit more, but deep dish wheels? Have a look at these....

Fairly wide huh ?

Oh, don't ask.

Because I didn't , but they were wide !!

Tony.

 

[Antm72]

Think theres many varibles here my last Z had a set of 18x8.5j wheel with an offset of 38 the front fit was fine but saying that i ran coilovers and as the body of a coilover sits alot lower than stock, off set can vary on set up . It did clear without spacers at the front but the tolerance was mm.
The rear if i remember was spaced hubcentrically possibly 10 or 20 mm to get the arch filled so as withalot of bmw's a staggered set up is required for a stock fit



Gave a great look and a great fit without any fouling issues

 

[zedonist]

Hi Tony,

Love the American Muscle, my favourite that one...

On the topic of the Police, they don't like frying bigger fish and would definitely prefer to pull you over for poke violation than catch a thieving git...reason being one brings in revenue the other just spends it...