Z4 (non-M) Definitive Wheel Spec Thread

[3GFX]

Originally Posted by miscbrah

How so? Isn't stock rear8.5" on a 3.0si?

Yup, not sure why I thought it was 9.5".

Still go, staggered and get some bigger rubber in the rear. Rear wheel cars like ours beg for a staggered set

[iShimy]

Hi,
I have inherited some Vossen CVT, Gloss Graphite, front 19"x8.5 ET40, which are fine.
However the backs are 19"x10 ET50, sadly they don't fit well rubbing the plastic guard on the inside. The tyre shop said I would need to cut the plastic guard and put a spacer for it to work. I freaked out and ran for my life. Any advise / help on what exactly I can do would be appreciated, thanks. They said if I used a 8mm spacer put 265 tyres it will be sitting beyond the fender, by this time I was half way down the road

[3GFX]

Run negative camber to get them to fit (but that would cause handling issue and major tire wear).

"SOME" wheels can be lightly machined to reduce ET. Couldn't tell you where to go, but it is occasionally an option.

[snowfarmer]

I have a set of Style 281 18x8 ET30 wheels, square setup on 225/40 tires.

Will they fit on a 2007 Z4 3.0si coupe? The style 281's extend 17mm front and 14mm rear further than the style 203's on the car now.

The style 281 wheels are the winter wheels from my 335i that I'm replacing with a Z4 coupe. I'm hoping that I can keep them to run as the winter setup on the Z4. If not, c'est la vie, I'll start hunting for a new set of winter rims.

[3002 tii]

Originally Posted by iShimy

Hi,
I have inherited some Vossen CVT, Gloss Graphite, front 19"x8.5 ET40, which are fine.
However the backs are 19"x10 ET50, sadly they don't fit well rubbing the plastic guard on the inside. The tyre shop said I would need to cut the plastic guard and put a spacer for it to work. I freaked out and ran for my life. Any advise / help on what exactly I can do would be appreciated, thanks. They said if I used a 8mm spacer put 265 tyres it will be sitting beyond the fender, by this time I was half way down the road

Throw on a spacer to push away from the plastic but run some negative camber to tuck under fender.

[Mr. Monday]

What are the widest front and rear 18" wheels and tires I can strap on the Z4. Could I fit 9" front and 10" rear? What offset would I need?
I would love to have 275 or 285 rear tires.

I am planning to add some power so I will need as much grip as possible.

[3002 tii]

Originally Posted by Mr. Monday

What are the widest front and rear 18" wheels and tires I can strap on the Z4. Could I fit 9" front and 10" rear? What offset would I need?
I would love to have 275 or 285 rear tires.

I am planning to add some power so I will need as much grip as possible.

Depends on suspension but I ran 9.5 et30 with 255 rs3's up front with -2.7* camber. You might be able to run 265 front and rear with the same wheel width/offset if you have more camber dialed in but 275 is unlikely.

[3GFX]

Originally Posted by Mr. Monday

What are the widest front and rear 18" wheels and tires I can strap on the Z4. Could I fit 9" front and 10" rear? What offset would I need?
I would love to have 275 or 285 rear tires.

I am planning to add some power so I will need as much grip as possible.

If you're keeping the stock fender width 265 would be the max you could go. Sure the rear at 275 may seem like more rubber but the amount of camber you would have to dial in would mean much less of an actual contact patch. 275's CAN fit. But you need the perfect offset. Take a wheel off and get in there with a tape measure.

The front, can't manage more than 245 imho, just not enough room in that wheel well.

[3002 tii]

Originally Posted by 3GFX

If you're keeping the stock fender width 265 would be the max you could go. Sure the rear at 275 may seem like more rubber but the amount of camber you would have to dial in would mean much less of an actual contact patch. 275's CAN fit. But you need the perfect offset. Take a wheel off and get in there with a tape measure.

The front, can't manage more than 245 imho, just not enough room in that wheel well.

I got 255s to fit up front pretty easily and didn't require crazy amounts of camber.

[3GFX]

Originally Posted by 3002 tii

I got 255s to fit up front pretty easily and didn't require crazy amounts of camber.

That's a good thing, I had lots of rubbing with 245, but the offset may not have been correct. If you haven't already...post your specs!

[3002 tii]

Originally Posted by 3GFX

That's a good thing, I had lots of rubbing with 245, but the offset may not have been correct. If you haven't already...post your specs!

Few posts up but 9.0-9.5 up front with 30 to 35 offset, you'll need about -2.5 or more. Key is to keep overall diameter within spec of 25" else you'll rub front liner with anything taller.

[jns_e85]

Originally Posted by 3002 tii

I got 255s to fit up front pretty easily and didn't require crazy amounts of camber.

Second this. The misses runs 255/40/17 on 17X8.5 Kosei K1 square for autocross with no issues. No spacers or fender mods what so ever. Camber pins were pulled in the front, and am sitting at -1.8 camber.

[Twixboy]

Originally Posted by 3GFX

That's a good thing, I had lots of rubbing with 245, but the offset may not have been correct. If you haven't already...post your specs!

Both me and unluky have the same model car as you and we are running 245/35-18 on our fronts with plenty of clearance without adjusting the camber. I'm lowered on Eibachs and use a small 5mm spacer up front (its actually 7mm after you take into account the extra 2mm offset from my aftermarket wheels). I believe unluky has H&R's and uses a 15mm spacer up front. The key is to put it on a 8" rim. Did you try using a 8.5-9" rim?

[atif7x7]

Need some help here -

I am picking up a set of CSL Reps 19 without tires.

I have leftover tires in new conditions from a Mustang:

The fronts are 255/40/19
Rears: 275/40/19

Will I be able to use these tires on the rims for a z4 3.0 si with sports suspension? The car is not lowered - stock suspension setup.

Any advice would be great!

Thx!

[dbarton62]

I doubt those tires will work. But the rim width and offsets will tell you whether they have a chance of fitting

[atif7x7]

Originally Posted by dbarton62

I doubt those tires will work. But the rim width and offsets will tell you whether they have a chance of fitting

Rims:

Front: 19 X 8.5 ET 40 (will have the 255/40 tires on it)
Rears: 19 X 9.5 ET 33 (Will have the 275/40 tires on it)

Let me know if this would work ?

[dbarton62]

Check these calculators
http://www.1010tires.com/Tools/Tire-Size-Calculator
http://www.1010tires.com/Tools/Wheel-Offset-Calculator

[The HACK]

Originally Posted by atif7x7

Will I be able to use these tires...

No. Those tires are over 2.5” larger in diameter, more than 10% larger overall. It’d be crazy to even try it IMO. They’ll likely rub because they’re more than 1.25” closer to the fender just based on radius along, plus another 3/4” closer to the fender axially.

No way in hell would I even consider it no matter what the wheel size and offset is.

[proboner]

Hey everyone. About to get a new wheel/tire combo and looking for some experienced opinions before everything is purchased and mounted.

Planned setup- Front: 19x8.5 +35 with 225/40/19 tires. Rear: 19x9.5 +35 with 255/35/19 tires.

Really I have 2 questions... will there be any issues with the offset on these? I'm hoping none of it will stick outside the fenders. Secondly, do you think my tires will cause rubbing issues? Considering the Z4M's run similar size tires I figured it wouldn't be an issue, especially since I'm at stock height.

Thanks!

[dbarton62]

Originally Posted by proboner

Hey everyone. About to get a new wheel/tire combo and looking for some experienced opinions before everything is purchased and mounted.

Planned setup- Front: 19x8.5 +35 with 225/40/19 tires. Rear: 19x9.5 +35 with 255/35/19 tires.

Really I have 2 questions... will there be any issues with the offset on these? I'm hoping none of it will stick outside the fenders. Secondly, do you think my tires will cause rubbing issues? Considering the Z4M's run similar size tires I figured it wouldn't be an issue, especially since I'm at stock height.

Thanks!

I had the same specs in 18”.

You may want to put a 10mm spacer on the fronts to bring them flush.
I did and had zero rubbing issues.
The rear will require adjustable camber arms as this setup will poke a bit and you will need to add neg camber to compensate. I ran 2 degrees.
I do get inner fender rub on deep road dips but never any fender rub.

FYI
I wore out the inner edge of my rears in 10k miles on that setup.
I have since gone to a 9” et 35 Rear rim so I can run less camber.

[proboner]

Shite, good to know. I haven't actually purchased the wheels yet, just the tires. I'll have to see if I can get them in 9" instead...

[proboner]

Originally Posted by dbarton62

I had the same specs in 18”.

You may want to put a 10mm spacer on the fronts to bring them flush.
I did and had zero rubbing issues.
The rear will require adjustable camber arms as this setup will poke a bit and you will need to add neg camber to compensate. I ran 2 degrees.
I do get inner fender rub on deep road dips but never any fender rub.

FYI
I wore out the inner edge of my rears in 10k miles on that setup.
I have since gone to a 9” et 35 Rear rim so I can run less camber.

So I currently have Style 224 wheels on my car, which look to be 9" wide with +30 offset in the rear. Seems to be pretty much spot on fitment wise. That would essentially be the equivalent of a 9.5" wide wheel with a +35 offset (technically +1mm). So in the end I think I'll be alright with it! Great success!