Fitment Question on 3.0i

Hi all,

I want to buy new wheels for my E85 3.0i. I have my heart set on Aodhan AH02s as they are in my budget and look amazing! I've been trying to figure out wheel sizing, but am not too knowledgeable in the topic, hence I am asking for the opinion from those who have experience.

Aodhan AH02 specs:
18x8.5 et35 front
18x9.5 et35 rear

Question 1:
Based on forums, the fronts should be flush, but the rears will poke. I just wanted to confirm this?

Question 2:
If the rears do indeed poke, I could go 18x8.5 et35 all round. I've seen on the forums that most people go with staggered setups, so would the handling characteristics of a square setup be drastically worse than a staggered setup?

have a play on willtheyfit.com, that'll tell you the exact amount that the wheels will stick out. the standard wheel specs are 18x8 ET47 front, and 18x8.5 ET50 rear.

the stagger comes from the tyres, not the wheels... if you do fit a square set up of 8.5s all round, you could still fit standard tyre sizes of 225/40 and 255/35, and keep the stagger.

I don’t agree with that. The stagger comes from the wheels, i.e. 8J front vs 8.5J rear. True you can introduce an element of stagger by putting different sized tyres on the same sized wheel, but I reckon the handling characteristics would be subtly different. 255s on 8J is quite a “loose” fit.

I'm running on a 2003 3.0

Front 225/40 R18 92W
Rear 255/35Z R18 94W

I've been looking for a set of alloys lately and didn't realise it wasn't as straight forward as it used to be with fitments etc.... Last time I bought alloys was 15 years ago and they were nothing fancy. I remember alloys being quite universal. Has it changed? When looking on websites and you filter to make and model, I don't like all the choices. What's the downside of a square set up against staggered?

I'll try my best to answer all your questions:

1. I was 3 years old 15 years ago so I don't know if anything has changed, but I can say that wheels aren't universal. You have to be careful of offset from the wheel hub as that will impact how far in or out of the fender your wheels are. Offset is one thing, but doesn't reflect the affect of wheel width on the spacing from the wheel hub. For example, 18x9.5 et35 might sit in a similar position compared to 18x9 et40 (that's not actually true, it's just a hypothetical example).

2. A square setup generally induces more oversteer, which is preferred on a racetrack but could be harder to control on backroads and daily driving. Staggered induces understeer, which is safer to control, but not preferred on track. Most Z4s come staggered from factory, but my oem wheels (style 200) were square from factory. I want to have more rubber in the back so I'm leaning towards staggered.

Nice one. Thanks mate. I'll be sticking with the staggered set I'm sure. Gives me a clearer picture as I've been driving a family car for the last 15 years, it's been a while since I've had to think about anything too much.

With a car as light as a Z4 on the tyre widths we run there's nothing much in it between square and staggered. I run the standard staggered 18s and, under hard braking, the 255s give the ABS something to think about!

It's not super hard either. Several of the preferred vendors will let you select your car and they will provide you with wheels that are known to fit. For example, Turner, or ECS. I'm sure there are others.

Also, it's pretty easy to see what OEM wheels fit a car and then looking up their backspacing on the web.

Also, I'll say internet info isn't always perfect. I was sure my Style 42's would not fit based on the internet discussions of "acceptable" offsets (Also Turner says they don't fit). According to my measurements they would be just flush... I ordered some used cheap versions as an experiment... they fit, and now I wish I had ordered a set that was already refurbished.... oh well. Good problems.

So for example on the front I'd say you're good with any 8" wide wheel that's from 47 - 20 mm offset. There are other guides that are less tolerant and suggest 47 - 35 mm offset on an 8" wheel.