[cstavaru]

Originally Posted by okolisr

I haven't seen this mentioned this yet, but I always learned that the main performance benefit from larger-diameter wheels (with lower-aspect-ratio tires to keep the same overall diameter) is NOT because of the larger wheel size, rather it's because of the lower aspect ratio of the tires which results in REDUCED TIRE SIDEWALL HEIGHT. With reduced sidewall height, tires do less flexing and floating while cornering, for better stability and road contact.

This is not true. If you look closely, the BMW Motorsport race cars have 18" Advan RS wheels (or custom BMW style). Also look at Formula 1 cars. Too little sidewall height results in loss of grip. Plus, larger wheels means that the wheel barrel must travel at a higher speed (because it is farther from the wheel center) which increases the force needed to rotate the wheel. Larger wheels = less performance, but better looks.

[Red Bread]

F1 has 15" wheels because Max Mosley says so. But yeah, even LeMans cars tend to run 18's, without as many regulations as F1.

[claykin]

Originally Posted by MacAttackBMW

I prefer the look of the 19's. Agree that the look is the main factor but given then staggered size and slightly bigger footprint on the road, I don't agree there is no performance impact. Sure, they may be slightly heavier but given that they are forged alloys - that's negligible. You are good either way but let's not knock the 19's!

Where did you read the 403M wheels are forged aluminum? I suspect the option would be more than $800 if the 18s were cast and 19s forged.

[SamS]

I like the 18" 400M wheels much better. There is zero performance benefit to the 19s, if anything they are a cost and performance hindrance. I normally get the biggest OEM wheel possible, but it seems the 19" (and 20" for that matter) are strictly a cosmetic upgrade, and will be a detriment to ride quality.

[clarence]

Originally Posted by claykin

Where did you read the 403M wheels are forged aluminum? I suspect the option would be more than $800 if the 18s were cast and 19s forged.

They're not.
From http://felgenkatalog.auto-treff.com/, the 400M weighs 11.8kg whereas the 403M weighs over 13kg.

[draco4691]

19" M sport wheels +1

[SamS]

Originally Posted by clarence

They're not.
From http://felgenkatalog.auto-treff.com/, the 400M weighs 11.8kg whereas the 403M weighs over 13kg.

Good site, I always forget about it.

Shows the 403M weigh 3lbs more per wheel than the 400M. And that doesn't take into account any increase in tire weight of the 19" version.

[justinnum1]

I like the design and how they look, but i dont think it makes sense to pay extra money and lose performance. Thats extra weight where you dont want extra weight.

[SamS]

Originally Posted by justinnum1

I like the design and how they look, but i dont think it makes sense to pay extra money and lose performance. Thats extra weight where you dont want extra weight.

Exactly. And I'd rather tighten up the suspension (M-adaptive) and have some extra sidewall cushion on the 18". Otherwise you risk your fillings rattling out when you hit every seam in the road.

[FlyByNite]

19's!

[Mrcarcrazy]

The 19's look so much better in my eyes. Since this is a family sedan theoretical "performance differences" are not a valid statement on either end IMO (and I'm always right, so don't bother trying to sway me).

With the 18's the car needs to be lowered to look right, on the 19's it looks great as is. Not to mention with the 19's everyone knows you are hot shit. 19's are a requirement to be awesome...sorry guys, but it's like having a 328.

[justinnum1]

Originally Posted by Mrcarcrazy

The 19's look so much better in my eyes. Since this is a family sedan theoretical "performance differences" are not a valid statement on either end IMO (and I'm always right, so don't bother trying to sway me).

With the 18's the car needs to be lowered to look right, on the 19's it looks great as is. Not to mention with the 19's everyone knows you are hot shit. 19's are a requirement to be awesome...sorry guys, but it's like having a 328.

Cant take a anything you say seriously anymore. Sorry.

[pkimM3r]

Originally Posted by okolisr

The bottom line is that even though I do faster cornering in my BMW than 95% of drivers, I don't need the "ultimate" capability. The 18" 400M wheels are plenty good enough.

And they look great.

professional racer?

[Mrcarcrazy]

Originally Posted by justinnum1

Cant take a anything you say seriously anymore. Sorry.

It's probably best, since the majority of my posts are placed entirely to entertain myself.

I will say though, that if you're looking for all out performance and running runflats, you should take a second look at that.

[JUSKIDN]

I like both but more partial to the 18's because thats what i have

[WilliCO]

Originally Posted by pcbrew

M-Sport 18s ARE staggered


Same staggered widths as the 19s, just slightly higher profile.
403M are 225/40 front and 255/35 rear

Agree.

IMO, as regards looks - the tire width makes a lot more difference than the wheel diameter. 18" is a large enough wheel to look good on the F30 body. A 19 may or may not look better, but unless you're looking at two cars side by side having each, you won't see the 18 as a "small" wheel.

Having those wide 255s in the rear is what makes the car look muscular, again IMO. 275 would be even better.

[MaestroAl]

When the first M Sports arrived at my local dealer, I went into their lot with my guy and looked at them all, having been previously adamant I'd get 18s. Then I saw a car with 18s next to a car with 19s and suddenly 19s were very, very high up on my must have options list.

I was robbed

In isolation, the 18s look awesome. Next to the 19s they look wrong. But since nobody else on my road, no wait: estate, no wait: town has an F30 M Sport then I coulda got 18s and been very happy with them

[TheObviousChild]

Originally Posted by MaestroAl

When the first M Sports arrived at my local dealer, I went into their lot with my guy and looked at them all, having been previously adamant I'd get 18s. Then I saw a car with 18s next to a car with 19s and suddenly 19s were very, very high up on my must have options list.

I was robbed

In isolation, the 18s look awesome. Next to the 19s they look wrong. But since nobody else on my road, no wait: estate, no wait: town has an F30 M Sport then I coulda got 18s and been very happy with them

Same here. I went to the dealer with the intention of ordering 18's. They had a red sportline with 19's....i was sold!

[DerekS]

Originally Posted by SamS

I like the 18" 400M wheels much better. There is zero performance benefit to the 19s, if anything they are a cost and performance hindrance. I normally get the biggest OEM wheel possible, but it seems the 19" (and 20" for that matter) are strictly a cosmetic upgrade, and will be a detriment to ride quality.

Yes, so true !!! 19s are also heavier than 18s.

[Seagull]

Originally Posted by Mrcarcrazy

It's probably best, since the majority of my posts are placed entirely to entertain myself.

I will say though, that if you're looking for all out performance and running runflats, you should take a second look at that.

Someone who truly understands the internet, and how to enjoy it!

[iwannabimmer]

I like the design of the 18s but I think the F30s look better with 19s in terms of size. Some aftermarket wheel company should make replicas of the 18s design in size 19.

[zibawal]

OP would you like to swap for 19 incl tires? Lol