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[Rookie2]

Hi all,

Why do Bimmers always have a staggered setup?
Is it for handling or aesthetics? What are the pros and cons if profiles are the same for front and rear?

Am driving a '10 E90 M3...is there a maximum profile allowed?

If staggered is it advisable to have 20 less in the front? (Eg 255/xx and 275/xx or 265/xx and 285/xx)

What offset would create a flushed look? Is offset generic or specific to brand/model of rim?

Would changing to aftermkt springs or coilovers change the look if say u are on stock springs and having a flushed look to start with?

Apologies for so many questions.....new to all these.

Tks alot.

[FRFNUGN]

The big reason is for handling. On rear wheel drive cars, oversteer is more likely to occur. Since most drivers are assumed to be incompetent by manufacturers, it is desirable for them to balance the car such that understeer will happen before oversteer (since it's safer/easier for terrible drivers to control). The easiest way to make sure understeer is more prominent than oversteer is to have less grip in the front, i.e. skinnier tires.

Pros of a non-staggered setup are better front-end grip (equal to rear), less understeer, balanced setup. Cons are you'll be more likely to crash into the tree backwards and not see it coming, whereas with the staggered setup you'll see the tree you're about to hit. Also, for winter, a sqaure setup is highly beneficial, as the rear wheels will drive in the same path as the front, which means they won't have to cut through snow and will have a better view of the road to grip.

In general, I think a 20mm width difference is preferred to keep things close, but when I bought my car it had 265 front 305 rear tires, so 40mm, and it was fine (just even more understeer since rear grip was so great compared to front). 275/35/18 front is about the largest profile you'll get away with on stock suspension. 305/30/19 works on the rear with very minor rubbing. Profile depends on wheel diameter too as for what you can get away with (275/35/19 would be too big in front, but 305/30/18 would fit with no rubbing probably* in the rear).

[Rookie2]

Thanks for the explanation FRFNUGN!

Guess i'll go for staggered setup since I dont track, my wife does the groceries runs, and I the occasional spirited street driving. Ü

What about offsets? Generic number or rim design dependent?

And if one is to view the car from the front or back, any safety, handling issues, etc if the front wheels protrude out more than the rear and vice versa? Or is it better for front n rear to be aligned? (The front fenders seem to protrude out more than rear)

Thanks!

Originally Posted by FRFNUGN

The big reason is for handling. On rear wheel drive cars, oversteer is more likely to occur. Since most drivers are assumed to be incompetent by manufacturers, it is desirable for them to balance the car such that understeer will happen before oversteer (since it's safer/easier for terrible drivers to control). The easiest way to make sure understeer is more prominent than oversteer is to have less grip in the front, i.e. skinnier tires.

Pros of a non-staggered setup are better front-end grip (equal to rear), less understeer, balanced setup. Cons are you'll be more likely to crash into the tree backwards and not see it coming, whereas with the staggered setup you'll see the tree you're about to hit. Also, for winter, a sqaure setup is highly beneficial, as the rear wheels will drive in the same path as the front, which means they won't have to cut through snow and will have a better view of the road to grip.

In general, I think a 20mm width difference is preferred to keep things close, but when I bought my car it had 265 front 305 rear tires, so 40mm, and it was fine (just even more understeer since rear grip was so great compared to front). 275/35/18 front is about the largest profile you'll get away with on stock suspension. 305/30/19 works on the rear with very minor rubbing. Profile depends on wheel diameter too as for what you can get away with (275/35/19 would be too big in front, but 305/30/18 would fit with no rubbing probably* in the rear).

[FRFNUGN]

Originally Posted by Rookie2

Thanks for the explanation FRFNUGN!

Guess i'll go for staggered setup since I dont track, my wife does the groceries runs, and I the occasional spirited street driving. Ü

What about offsets? Generic number or rim design dependent?

And if one is to view the car from the front or back, any safety, handling issues, etc if the front wheels protrude out more than the rear and vice versa? Or is it better for front n rear to be aligned? (The front fenders seem to protrude out more than rear)

Thanks!

A big benefit of going square (non-staggered) is being able to rotate your tires from front to back, as the backs generally wear much quicker. You may want to take that into consideration for longer tire life / less money spent on tires.

I can't answer with certainty on offsets (other than the lower the number, the further they'll stick out from the hub) or front-to-rear track width changes, but I'd wager that high-speed stability will be better with wider rear track than front. Use this link to see how different size wheels / offsets will fit: http://www.rimsntires.com/specspro.jsp.

Stock wheels are:
Front
18x8.5 et29 (219M)
19x8.5 et29 (220M)
19x9 et31 (ZCP/359M)

Rear
18x9.5 et23 (219M)
19x9.5 et23 (220M)
19x10 et25 (ZCP/359M)