Ride Quality - 18's versus 19's

[RickMonet]

How much is Ride Quality improved going with 18 inch wheels opposed to the optional 19 inch?

Would it be really noticeable - or pretty much insignificant difference?

[voodoogeek]

I'm not a pro, but I'd say you'll notice the difference. had 18" on my 335 and then bought 19" for the summer tyres and yes, it was a noticeable difference. GF scratched them after 3 days, but that's another story.

I went for the black 19" on the M4 and will soon have to replace them (delivery of the car is due end of September, levaing me 1-2 months with summer tyres... just enough for run-in and then some) with the standard 18" with winter tyres. the 19" will then be back on by April 2015.

on the other hand, I really like a "hard ride" (no pun intended) so I was absolutely fine with the 19" comfort.

[BlackLight]

Did you have the same tire brand on each size?

[RickMonet]

Originally Posted by BlackLight

Did you have the same tire brand on each size?

Yes - considering the same tire choice. If the daily driving ride quality is significantly stiffer with 19 inch wheels opposed to 18's, then perhaps 18's make better choice for daily driving?

However, if there is only a minor improvement going with 18's - then I prefer the look of the 19 inch wheels.

I have little experience swapping out wheels - but know this is common practice for others on this forum. I was hoping to learn from their previous experiences.

[Canyon_Dancer]

In the past, there wasn't much difference between the two at all to me, so I can't see that being any different with the F8X.

[SOM3]

You can't really tell a difference in everyday driving. Maaaaybe at the racetrack.

[shortseller]

Seems as though a lot of high end performance auto manufactures have gone to 19s as standard, even as far as offering 20s as an upgrade. I ran 19s for 5 yrs on my 335i e92 with sport pkg and it was fine as a DD and it even had RFTs. But will say in winter situations 18s or even 17s will do best based on experience.

[JoeFromPA]

During my test drive, I noticed road irregularities that I believe were transmitted with NVH on the 19s that I BELIEVE would be eliminated with the 18s. The car still rode quite well, but I felt minor undulations and "busyness" that probably should have been dialed out but was not due to the lack of sidewalls.

From a daily driver and frequent driver standpoint, the 18s should ride better, wear slower, and cost less to replace.

Lastly, one thing I'll note is that I spend the majority of my driving time (99.9% to be exact) on real world roads. These involve lots of unsmooth pavement.

I find better traction and driving satisfaction out of vehicles that are able to better absorb mid-corner road undulations without upsetting the chassis. The M3 has the best chassis to date, but a bit of give can actually improve performance in these situations and I think the 19s take a bit of that give away.

Just my .02 and based solely on a very good test drive.

Edit: Just to be clear, after seeing some other comments, this isn't about 18s vs 19s. It's about sidewall height and construction. It's not the 19s are inherently some lesser design, it's that by going to 19s you get a significantly more rigid sidewall that is 33% (IIRC) smaller in height.

[shortseller]

Originally Posted by JoeFromPA

During my test drive, I noticed road irregularities that I believe were transmitted with NVH on the 19s that I BELIEVE would be eliminated with the 18s. The car still rode quite well, but I felt minor undulations and "busyness" that probably should have been dialed out but was not due to the lack of sidewalls.

From a daily driver and frequent driver standpoint, the 18s should ride better, wear slower, and cost less to replace.

Lastly, one thing I'll note is that I spend the majority of my driving time (99.9% to be exact) on real world roads. These involve lots of unsmooth pavement.

I find better traction and driving satisfaction out of vehicles that are able to better absorb mid-corner road undulations without upsetting the chassis. The M3 has the best chassis to date, but a bit of give can actually improve performance in these situations and I think the 19s take a bit of that give away.

Just my .02 and based solely on a very good test drive.

Edit: Just to be clear, after seeing some other comments, this isn't about 18s vs 19s. It's about sidewall height and construction. It's not the 19s are inherently some lesser design, it's that by going to 19s you get a significantly more rigid sidewall that is 33% (IIRC) smaller in height.

Does anyone know for a fact that BMW dials in the car with standard 18s in mind or the upgrade 19s, (reason being)as it reaps more benefit, $, with the ability to sell an upgraded braking systems as well, another 8k if I remember right?

[JoeFromPA]

Don't forget that the 18" wheels are notably less weight than the 19s (I can't comment on tires since IDK and tirerack is not accurate). I believe it's 3.3 pounds per wheel in the front and ~2.3-2.6 pounds per wheel in the rear.

[khanyam4]

The 18 will be more comfortable. 19 are a good compromise between looks and performance, with that said I'm very please with design and weight of the standard 18's and optional 19's.

[baalzephon]

FWIW, I gotta say, on the 19s I *really* feel how crappy the roads are in NYC, in a way I didn't expect. I'd love the feel if we had good roads, but it amplifies the bad roads here in a major way I didn't expect.

[shortseller]

Whatever choice you make, 18 vs 19, you have to like the idea the 18s are forged, looks quite good and are a standard offering, ie not extra cost!

[Canyon_Dancer]

Originally Posted by JoeFromPA

Don't forget that the 18" wheels are notably less weight than the 19s (I can't comment on tires since IDK and tirerack is not accurate). I believe it's 3.3 pounds per wheel in the front and ~2.3-2.6 pounds per wheel in the rear.

...but how much are the 18" tires vs the 19" tires?

[JoeFromPA]

Here's all the weight info I could pull together quickly:

18” http://f80.bimmerpost.com/forums/sho...php?p=16426788
Front: 44.00lb w/ tire
Rear: 48.25lb w/ tire

19” wheel and tire: http://f80.bimmerpost.com/forums/sho...el+tire+weight
Front = 45.90 w/ tire
Rear = 49.85 w/tire

Weights of Rims per BMW: http://f80.bimmerpost.com/forums/sho...php?p=16426788

18" 513M
front = 8.92kg (19.6lbs)
rear = 9.44kg (20.8lbs)

19" 437M
front = 10.4kg (22.9lbs)
rear = 10.6kg (23.4lbs)

[Canyon_Dancer]

Originally Posted by JoeFromPA

Here's all the weight info I could pull together quickly:

18” http://f80.bimmerpost.com/forums/sho...php?p=16426788
Front: 44.00lb w/ tire
Rear: 48.25lb w/ tire

19” wheel and tire: http://f80.bimmerpost.com/forums/sho...el+tire+weight
Front = 45.90 w/ tire
Rear = 49.85 w/tire

Weights of Rims per BMW: http://f80.bimmerpost.com/forums/sho...php?p=16426788

18" 513M
front = 8.92kg (19.6lbs)
rear = 9.44kg (20.8lbs)

19" 437M
front = 10.4kg (22.9lbs)
rear = 10.6kg (23.4lbs)

Damn those 18" tires are heavy. Thanks for compiling that information. The impetus for my question derived from noticing that the 20" Avant Garde's w/tires that I just sold off of my 335i were lighter than the OEM 403M's with tires.

[JoeFromPA]

Yep, no problem. It's funny, heavier tires are definitely not what you want from a performance standpoint - but I'm willing to bet that weight is going into an outstanding carcass and sidewall that will hold up better to abuse AND absorb better imperfections.

Though the total unsprung rotating mass is less with the 18s, I'm betting the fact that the 18s tires are heavier will balance it out considering they are a greater distance from the axis.

[RickMonet]

Originally Posted by JoeFromPA

During my test drive, I noticed road irregularities that I believe were transmitted with NVH on the 19s that I BELIEVE would be eliminated with the 18s. The car still rode quite well, but I felt minor undulations and "busyness" that probably should have been dialed out but was not due to the lack of sidewalls.

From a daily driver and frequent driver standpoint, the 18s should ride better, wear slower, and cost less to replace.

Lastly, one thing I'll note is that I spend the majority of my driving time (99.9% to be exact) on real world roads. These involve lots of unsmooth pavement.

I find better traction and driving satisfaction out of vehicles that are able to better absorb mid-corner road undulations without upsetting the chassis. The M3 has the best chassis to date, but a bit of give can actually improve performance in these situations and I think the 19s take a bit of that give away.

Just my .02 and based solely on a very good test drive.

Thanks Joe for the insight from your test drive.

My car will be a daily driver and never see the track. I currently have Black 19's on my order. For everyday comfort - I wonder if the 18's are a better choice.

[Canyon_Dancer]

Originally Posted by JoeFromPA

Yep, no problem. It's funny, heavier tires are definitely not what you want from a performance standpoint - but I'm willing to bet that weight is going into an outstanding carcass and sidewall that will hold up better to abuse AND absorb better imperfections.

Though the total unsprung rotating mass is less with the 18s, I'm betting the fact that the 18s tires are heavier will balance it out considering they are a greater distance from the axis.

Or it could be that run-flats are heavier than a standard construction tire.

[JoeFromPA]

Originally Posted by Canyon_Dancer

Or it could be that run-flats are heavier than a standard construction tire.

How does that apply here? There are no run-flats involved, 18s or 19s...

[JoeFromPA]

Originally Posted by RickMonet

Thanks Joe for the insight from your test drive.

My car will be a daily driver and never see the track. I currently have Black 19's on my order. For everyday comfort - I wonder if the 18's are a better choice.

I personally believe 18s are the better choice for track as well. See Karussell's thread on tracking the 18s on the 'Ring, and he's an extremely experienced racer.

The 19s are a very nice option for visible purposes or CCB upgrades.

[Canyon_Dancer]

Originally Posted by JoeFromPA

How does that apply here? There are no run-flats involved, 18s or 19s...

Sorry for the confusion. I was still referring to the example I presented.

Back to F8X specific stuff!