2007 Z4M Please help 18 to 17 inch wheel change

aloofbit · 06-25-2021, 01:19 PM

Hi, I recently got a cool 2007 BMW Z4 M! It's really fun but the ride is super brutal for Chicago roads.

The car has 100k miles and I have read that a few changes I can make are

to get a B6 shocks + struts (https://www.ecstuning.com/b-bilstein...-kit/mz4hdset/) and reuse the stock springs.
Change to smaller rim with taller sidewall tire

Currently the car has
rear: 275/35 ZR18 Pilot Sport 4s
front: 245/40 ZR18 Pilot Sport A/S 3+

I'm not sure how I can see rim size! But fitment seems really clean and would like to find news ones that are similar (will attach picture).

Can you please share what kind of rim / tire setup you have that might improve ride?

mmm-five · 06-26-2021, 08:13 AM

At that mileage I wouldn't be surprised if the suspension (springs, shocks/struts, bushes, etc.) are well past their best anyway...and the coupe was never a 'comfort-orientated' drive.

I wouldn't reuse the original springs...I'd either get new OEM ones, or aftermarket replacements.

If you do lower it, you'll have to be very careful of rubbing due to running 20mm wider tyres front & rear.

aloofbit · 06-26-2021, 12:28 PM

Quote:

Originally Posted by mmm-five

At that mileage I wouldn't be surprised if the suspension (springs, shocks/struts, bushes, etc.) are well past their best anyway...and the coupe was never a 'comfort-orientated' drive.

I wouldn't reuse the original springs...I'd either get new OEM ones, or aftermarket replacements.

If you do lower it, you'll have to be very careful of rubbing due to running 20mm wider tyres front & rear.

Ty! Is it better to get coil over so that it would be adjustable? I was not sure the coilover options for comfy driving as they all seem more race oriented

mmm-five · 06-26-2021, 01:19 PM

Coil overs with ride height adjustment will give you more adjustability as you can change the bump & rebound as well as the ride height…but they’ll probably be more expensive than standard replacements.

I find my Bilstein PSSS10 kit is much better than the OE suspension, even when it’s not of the softest setting…and it’s only on the hardest settings on track…and it’s quick to adjust from underneath the car.

Pyrat 2 · 07-03-2022, 10:09 PM

I've used the B6 Bilsteins on several BMWs in the past. They are my 'go-to' upgrade. Have transformed every car. I am just about to hit the buy button on a set for my new to me Z4M Roadster. Can you tell me what brand wheels you are running on your car with those tires? That way I can look up the likely size and offset.

Coi · 07-05-2022, 09:55 PM

Only issue with 17" wheels is potentially not clearing the brakes. Will have to get a design that has appropriate clearance for the barrel and spokes.

Apex makes 17" wheels that do clear original brakes on the Z4M. Their designs, which some consider a little derivate, have an OEM-like feel. They're also a forum sponsor and have a fitment guide: https://support.apexraceparts.com/hc...-Fitment-Guide

I personally plan to get 18" Apex wheels for my car some day, but haven't settled on a setup yet.

Pyrat 2 · 07-07-2022, 11:13 PM

Quote:

Originally Posted by Coi

Only issue with 17" wheels is potentially not clearing the brakes. Will have to get a design that has appropriate clearance for the barrel and spokes.

Apex makes 17" wheels that do clear original brakes on the Z4M. Their designs, which some consider a little derivate, have an OEM-like feel. They're also a forum sponsor and have a fitment guide: https://support.apexraceparts.com/hc...-Fitment-Guide

I personally plan to get 18" Apex wheels for my car some day, but haven't settled on a setup yet.

If you're planning to do so. You may want to move fast. I contacted them the other day and they said they were discontinuing a few fitments including 18x8.5 et35 on their FL5. This is a main go to fitment for the Z4 M.

Michael9218 · 07-21-2022, 05:44 PM

17" Apex wheels clear the brakes no problem. Arc-8's even clear my 355mm Stoptech Trophy brakes.

I'm running 17's on both my track car and street car. 17x9.5 et35 Arc-8's. On the track car I fit 275/40/17 tires square and on the street car that has Bilstein PSS10's I fit 255/40/17 square. To fill out the wheel wells I use a 7.5mm spacer in front and 15mm rear (requires studs).

I recently added the PSS10 suspension and second that recommendation for a street car (track car has MCS remote 3 way suspension. You don't want to know what that costs!).

06-25-2021, 01:19 PM	#1
aloofbit New Member 1 Rep 6 Posts Drives: BMW Z4 M Join Date: Jun 2021 Location: Chicago iTrader: (0)	2007 Z4M Please help 18 to 17 inch wheel change Hi, I recently got a cool 2007 BMW Z4 M! It's really fun but the ride is super brutal for Chicago roads. The car has 100k miles and I have read that a few changes I can make are to get a B6 shocks + struts (https://www.ecstuning.com/b-bilstein...-kit/mz4hdset/) and reuse the stock springs. Change to smaller rim with taller sidewall tire Currently the car has rear: 275/35 ZR18 Pilot Sport 4s front: 245/40 ZR18 Pilot Sport A/S 3+ I'm not sure how I can see rim size! But fitment seems really clean and would like to find news ones that are similar (will attach picture). Can you please share what kind of rim / tire setup you have that might improve ride? Attached Images
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06-26-2021, 08:13 AM	#2
mmm-five First Lieutenant 222 Rep 374 Posts Drives: 2006 Z4MC + 2015 320D M-Sport Join Date: Aug 2017 Location: Liverpool, UK iTrader: (0)	At that mileage I wouldn't be surprised if the suspension (springs, shocks/struts, bushes, etc.) are well past their best anyway...and the coupe was never a 'comfort-orientated' drive. I wouldn't reuse the original springs...I'd either get new OEM ones, or aftermarket replacements. If you do lower it, you'll have to be very careful of rubbing due to running 20mm wider tyres front & rear.
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06-26-2021, 01:19 PM	#4
mmm-five First Lieutenant 222 Rep 374 Posts Drives: 2006 Z4MC + 2015 320D M-Sport Join Date: Aug 2017 Location: Liverpool, UK iTrader: (0)	Coil overs with ride height adjustment will give you more adjustability as you can change the bump & rebound as well as the ride height…but they’ll probably be more expensive than standard replacements. I find my Bilstein PSSS10 kit is much better than the OE suspension, even when it’s not of the softest setting…and it’s only on the hardest settings on track…and it’s quick to adjust from underneath the car.
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07-03-2022, 10:09 PM	#5
Pyrat 2 Colonel 1418 Rep 2,560 Posts Drives: Rapidly from A to B Join Date: Jun 2005 Location: Chicago 'burbs or TN Smokies iTrader: (3) Garage List 2022 Porsche GT4 [9.64] 2018 Porsche GT3 [9.33] 2007 Z4 M Roadster [8.33] 2020 BMW X1 [0.00]	I've used the B6 Bilsteins on several BMWs in the past. They are my 'go-to' upgrade. Have transformed every car. I am just about to hit the buy button on a set for my new to me Z4M Roadster. Can you tell me what brand wheels you are running on your car with those tires? That way I can look up the likely size and offset. __________________ '07 Z4MR '22 GT4 '18 GT3 '16 GT4, '16 M2, '14 X1, '13 135is, '06 330i, '03 323 Ci, '01 330i, '99 M3 (RIP), '96 318is, some non-BMWs
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07-05-2022, 09:55 PM	#6
Coi First Lieutenant 289 Rep 323 Posts Drives: 21 X3 M40i, 07 Z4MR Join Date: Mar 2021 Location: Cal iTrader: (0)	Only issue with 17" wheels is potentially not clearing the brakes. Will have to get a design that has appropriate clearance for the barrel and spokes. Apex makes 17" wheels that do clear original brakes on the Z4M. Their designs, which some consider a little derivate, have an OEM-like feel. They're also a forum sponsor and have a fitment guide: https://support.apexraceparts.com/hc...-Fitment-Guide I personally plan to get 18" Apex wheels for my car some day, but haven't settled on a setup yet. Last edited by Coi; 07-06-2022 at 03:49 PM..
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07-21-2022, 05:44 PM	#8
Michael9218 Lieutenant 595 Rep 484 Posts Drives: 2007 Z4 M Coupe Join Date: Oct 2012 Location: Woodstock, GA iTrader: (0)	17" Apex wheels clear the brakes no problem. Arc-8's even clear my 355mm Stoptech Trophy brakes. I'm running 17's on both my track car and street car. 17x9.5 et35 Arc-8's. On the track car I fit 275/40/17 tires square and on the street car that has Bilstein PSS10's I fit 255/40/17 square. To fill out the wheel wells I use a 7.5mm spacer in front and 15mm rear (requires studs). I recently added the PSS10 suspension and second that recommendation for a street car (track car has MCS remote 3 way suspension. You don't want to know what that costs!).
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