Transitioning from 18-inch wheels to 16-inch wheels.

[tr4s]

Greetings everyone,

I apologise if this inquiry seems trivial; but, I am entirely inexperienced in this matter.


I possess an E92 320D Coupe equipped with 18-inch staggered wheels that were included with the vehicle.
I dislike the jarring ride they provide, and I have been informed that installing 16-inch wheels, together with the appropriate tires to preserve the correct diameter, will significantly enhance the vehicle's ride quality.
I informed my local tyre technician of my intentions, and he cautioned that it would disrupt the ABS sensors, alter the gear ratios, appear aesthetically unpleasing, and impair the vehicle's handling.

Will the 16-inch wheels enhance ride quality sufficiently for me to see a difference?
Should I adhere to the 18" wheels as the tyre specialist suggests, since replacing them with 16" wheels will disrupt the system?

I owned an E46 320ci with 16" wheels, and it was significantly more comfortable than this vehicle.

Thank you in advance for your responses.

[CleverPixel]

Affirmative, negative, uncertain. I have recently traversed this route, as the surrounding roads are in bad condition. The 19-inch rims result in a harsh ride, and the M-Sport specifications are prone to cracking, leading to air leaks and error codes.

The tyre expert is correct in asserting that installing larger tyres on current rims disrupts telemetry and may affect insurance, suspension clearance, and other factors.


Transitioning from run-flat tires (RFT) to conventional tires will yield a more supple ride. They are less expensive, more readily available, and repairable; however, it is prudent to seek a space-saver or an additional full-size rim for an onboard spare. RFT may perform adequately on smooth, clean roads, but becomes ineffective when driven on flat surfaces. In my experience, you can seal them if you identify the leak first, but not after they have been flattened and driven on.

Yes, you may go for 16" tires, since they will offer the maximum sidewall height, providing greater rubber contact between the road and rim, resulting in a more comfortable ride. You will significantly notice the improvement in ride quality. While you may observe a reduction in handling, based on my experience, the existing speed restriction and the absence of a Nuremberg track nearby render this mostly unimportant, especially considering that vehicles once exceeded 200 km/h on that circuit with 60-70 sidewall tires.

I replaced the staggered 19" run-flat M-Sport tires on my E93 with a $400 square set of 17" tires obtained from the wreckers. During my visit, I acquired a space saver from an E60, a compact scissor jack, and many normal wheel nuts to replace the locking nuts. I assumed that all BMWs utilise the same locking nut; nevertheless, the perpetrators may possess the key, making it still another trivial item to standardise in case of loss.

My primary challenge was locating a pair of 17" rims that I favoured, which also had an appropriate offset (ET) compatible with the vehicle. The 5x120 bolt pattern is prevalent among most BMW models manufactured post-2005, I believe. Numerous individuals designate 18" as the optimal size; nevertheless, in my opinion, it only provided an additional 15mm of rubber in wall height. 16 inches; I had not encountered a set until the 17 inches were installed on the vehicle, but for a 1992 model, they may appear somewhat diminutive. It is fundamentally a matter of personal preference. I transitioned from 225/35/19 8J-et37 and 255/30/19 9J-et39 to 235/45/17 7.5J-et37; as all tires maintained the same rolling circumference, the vehicle remains unaffected.

[CleverPixel]

To assist with ET and tyre dimensions, experiment with these.

[CleverPixel]

Determine the meaning of OE:

https://www.wheel-size.com/size/

[CleverPixel]

What tire size is most suitable for a rim with a J width?

[CleverPixel]

https://premiertiresandwheels.ca/pages/tire-size-guide?srsltid=AfmBOooRN5nmdN7zQUeT8NVjpVcELkk40D9GhJTJWVOuVUxpRRn6DAahttps%3A%2F%2Fwww.wheel-size.com%2Fcalc%2F%3Fwheel1%3D225-35-19X8ET37&wheel2=225-50-17X7ET47&fcl=50mm&scl=50mm&wcl=30mm&sr=0mmT

[CleverPixel]

comparing new trye size to old

https://tiresize.com/tyre-size-calculator/

[CleverPixel]

Verify that the new size complies with the vehicle's standards; ensure you enter your inputs first:

https://www.wheel-size.com/calc/

[Banman]

The E92 was never equipped with 16" wheels, so I am uncertain if they will accommodate the callipers. However, it did come with 17" wheels, so I recommend opting for those, since they will enhance comfort unless fitted with run-flat tires.

The factory's tyre sizes are as follows

[Banman]

https://www.realoem.com/bmw/enUS/showparts?id=WD12-EUR-05-2007-E92-BMW-320d&diagId=85_0051

[Ziinsig]

Indeed, the E92 320 is equipped with smaller brakes compared to the 330s that feature 19-inch wheels.

I now have 17-inch rims paired with 325 brakes on the 1993 model, which is identical to the 1992 model in this aspect. I will verify later today and inform you if a 16" will be suitable.

[Ziinsig]

Visually, I would assert that 16-inch wheels would be compatible with a 320 model, whereas RealOEM indicates that the 325 rotors measure 311mm in the front and 300mm in the rear. I remember that the 4-cylinder diesel engines were identical to the 6-cylinder petrol engines (specifically, my 325 donor brakes). There is a sufficient inch of clearance between the callipers and my 17-inch rims, allowing ample space for a 16-inch rim.

The 330d M-Sport rotors measure 330mm and 336mm, compatible with a 17-inch rim, but not with a 16-inch rim.

[Tactical]

My 320i was equipped with 300mm front discs and 17-inch wheels from the factory.
I acquired a set of pre-owned 330mm discs and callipers from the owner of a 130i who was upgrading to blue callipers.
The 17-inch wheels fit without any difficulty, however the 330mm discs significantly filled the space within the 17s, creating an aesthetically pleasing appearance.

[Tactical]

I have possessed an E92 320i equipped with 17-inch run-flat tires. I installed regular tires after the run-flats required replacement.
The riding was satisfactory on the highways of UK towns. I believe that equipping the car with 16-inch wheels would render it aesthetically unappealing, given its coupe design.


The E92 was offered with 17-inch wheels as an option, hence they would not provide any complications. The 17-inch tires I possessed were of a square configuration, perhaps 225/45/17, and those tires were significantly less expensive than the staggered setup on the rear.

The ride in my current 420i Msport with 18-inch run-flat tires is considerably firmer. I anticipate the day I can replace them with standard tires.

[Seconsu]

Open the door and examine the tyre pressure label. All tyre size possibilities are available there. Furthermore, it will have minimal impact on those dimensions; for example, my rear tires have a 40 profile instead of 35, yet I see no error indicators.

[Lemmand]

I would choose for 17-inch tires with standard specifications.