Hey forum,

The time has come for me to put some rims on the Crossfire, but I really don't know anything about how wheel sizing works.
I want to stay as close as possible to stock sizing but unfortunately, nobody makes any wheels that are an exact match for
our cars (if I'm wrong, please let me know). So I found some wheels that I really like that come in 18's and 19's. I've been
doing a lot of research, so can you experts let me know if I'm correct?

Crossfire stock wheel and tire sizing:
FRONT:
18x7.5"
5x112 (Bolt Pattern)
ET 35 (offset)
66.56 Bore
Tire 225/40/18

REAR:
19x9"
5x112 (Bolt Pattern)
ET 22 (offset)
Tire 255/35/19

The Wheels I WANT are the Niche M124 Milan (http://www.nicheroadwheels.com/milan-m124-w-33341.htm)
Here are the available sizes (http://www.nicheroadwheels.com/specs.cfm?id=8572)

The closest matching wheels they make for the Front are:
18x8"
5x112 (Bolt Pattern)
ET 42 (offset)
66.50 Bore

The closest matching wheels they make for the Rear are:
19x8.5"
5x112 (Bolt Pattern)
ET 48 (offset)
66.60 Bore

With this setup, I was going to get 10mm Spacers for the Front
And 30mm Spacers for the Rear to maintain proper clearances.

Is this correct? I know nothing about spacers and offsets, so I'm not sure if I'm calculating these things correctly. If correct, are 30mm spacers too big?
I've heard through the grapevine that spacers are a big no-no. Also, what size Lug Bolts will I need? Please help.

 

I'm now realizing that the bore for the front wheel is 66.50, which is .06mm TOO SMALL. Is this going to be a problem, or is that just some weird auto-motive way of rounding?

If it IS going to be a problem, would it be sensible to get THESE wheels and use a 5X112 to 5X4.5 spacer and a Hub Ring to adapt the bore from 72.6 back to 66.56?:
18x8"
5x4.5 (Bolt Pattern)
ET 40 (offset)
72.60 Bore

 

Very nice looking wheel, I always liked the look of a five spoke on the Crossfire. Take a look at Mandrus wheels. They have a similar wheel to the Niche M124 and there wheels are specifically made for Mercedes or the Crossfire and you may find backspacing very close or exact. Spacers do work well if they are good quality with tight tolerances in the hub areas, but if you can get away without having to use them, I think your better off. Hope this helped

 

Thanks. I've looked into Mandrus before and I really like their wheels, but they still don't offer anything in stock Crossfire sizing. They do offer everything in 18" and 19", but at the prices they're asking, I'd much rather go with something else if it's going to require extra work either way. Appreciate the recommendation though.

 

Mandrus Wilhelms here 19x8.5 and 20x10 .
i love em , perfect fit , i will look up the offset i have for you if you want/

 

[QUOTE=pazminoproject;890396]I'm now realizing that the bore for the front wheel is 66.50, which is .06mm TOO SMALL. Is this going to be a problem, or is that just some weird auto-motive way of rounding?


An inch is about 2.5cm, so an inch is 25 mm. The difference between 25.06mm and 25mm is smaller than anybody is measuring on wheels. That's about the fineness of a hair. Just my guess.

 

If it was me I would stay away from spacers if I could.
Several tire shops I have talked to, either would not touch the vechicle or would not put the spacers back on.

Niche targa and Essex has the offsets needed if I remember.

I searched for along time and ended up going with esr Sr 08
This is what I have.
In my thread I have pics showing clearance with wheels shoved into the Wells.
Drove front tire on rock pile, front drivers tire and rear passenger tire shoved into wells and frost pass and rear driver have a few inches of clearance under tires.

Front
Str sr08 18x8.5 30 offset machine silver.
235/40R-18 YOKOHAMA AVID ENVIGOR
Rear
Str sr08 19x10.5 20 offset, machine silver.
285/35ZR-19 CONTINENTAL EXTREMECONTACT DWS

And the esr was a hair lighter, not much, but atleast not heavier.
I was looking through weights also

Tsw has some good options also at good price with even lighter rotary forged wheels.

 

Wow, thanks Speedy! Your wheels look really nice.

At this point, I've done more research and it's pretty clear that if done correctly, spacers are not a bad idea at all.
There are professional race car/drift car drivers who use spacers. It's a common thing, I'm finding out.

I'm also finding that I'm going to HAVE to compromise somewhere on my dimensions. Either I have to get
wider wheels, taller wheels, or use spacers, and I'll probably need some adapters for bolt pattern and bore diameter
as well. There's just not a single wheel in existence that is a direct bolt-on and dimensional replacement for our cars.

I'm still kinda worried about the 66.50mm bore vs 66.56mm, so I emailed the manufacturer to see if this is a typo
on their end or if they really make wheels in sizes that are only .10mm apart (66.50 and 66.60 respectively).
It just makes no sense why Niche's 18-inch wheels would have a completely unheard of and useless bore diameter,
but their 19 and 20-inch wheels come in the common 66.60.

 

Here's the link to the Mandrus Wheel Fitment Guide for Mercedes-Benz models: CLICK

Select the 2004 SLK320 model (R170 chassis), which is the Crossfire chassis, and you'll find Mandrus wheels that are an exact fit w/o spacers. You can use this as a guide for other wheels to make sure they will fit w/o issues.

 

I really do like the Mandrus Wilhelms on the Crossfire. But I would probably stick with 18"/19" staggered wheels.

 

 

 

I wanted wider, silver, not taller or heavier
You can get a direct bolt on what ever you want, if you want to spend the $$$
If you seen the dates on my posts on my thread you see how long it took me to decide.
The esr wheels are a 114.3 bolt pattern that is chamfered to a 112, and the esr have a 73 bore, even with that I have not put my hub rings on yet and no vibration, I am using bolts, my local shop told me they have put wheels on 4 or 5 crossfires and they said they had vibration from all until the studded the hubs and used nuts and got rid of vibration.
Since you will be ordering new bolts anyway, might be a idea to just stud and nuts, they are easy just use locktite.
Keep a eye on the wheels you get if you need to get new bolts in a conical ball or beveled bolts.