[Tambohamilton]

+1, better mid corner balance with square setup. I don't care so much about accelerating out of corners

[RL18]

Originally Posted by lnxguy

Square all day for the tire rotations alone (Especially how the e90 in stock alignment specs likes to eat rear tires).

17x9 255/40 Indy 500s all the way around.

Like I said I’ve been running staggered and have gotten 3 years out of my nitto nt555 g2s and the fronts still have half tread, I do a lot of rolling burnouts. If you’re going through tires too fast you have an alignment issue. Toe should be as close to zero as possible. Would never do square on a rwd car, I would however on and awd car. This is my alignment specs though…

[Scubudo]

Originally Posted by RL18

Why go square on a rwd car? You’re better off staying staggered. Better handling characteristics. I’m planning on upgrading to 255/275 when get tires next. I’ve gotten 3 years out of my nitto nt555 g2 with aggressive driving , but only drive it in the summer

Take a picture of your tire wear in the rear on both sides please. And If you can remove both tires and post a side by side pic.

Will try to pull wheels and take pictures this weekend.

So...your summer driven only tires lasted 3 yrs. That equates to 18 months if you were to use your summer tires year round. That in itself is not very impressive.
How many miles are you getting per set of tires?

In the meantime...I will sit back and let everyone else argue staggered vs square.

[RL18]

Originally Posted by Scubudo

Will try to pull wheels and take pictures this weekend.

So...your summer driven only tires lasted 3 yrs. That equates to 18 months if you were to use your summer tires year round. That in itself is not very impressive.
How many miles are you getting per set of tires?

In the meantime...I will sit back and let everyone else argue staggered vs square.

Yeah the rears only, front have more than half tread. Considering how many rolling burnouts I do it’s impressive. Technically I could just buy new rears but I want to increase to 255/275 so I can get more traction.

There’s no argument when it comes to performance there’s a reason manufacturers do staggered setups on rwd cars. If your cheap you do square

[E85 Sport]

Originally Posted by Tambohamilton

+1, better mid corner balance with square setup. I don't care so much about accelerating out of corners

What size is your square setup? Wheels, tires, offset.

[Tambohamilton]

To be fair, I'm not actually square...just squarer than stock. F235 40 18, R245 40 18. Stock wheels. Currently ps5 front and PS4 rear, but the rear are due for replacement soon.

My suspension setup is a lot different from stock, and quite different from what's commonly recommended.

[lnxguy]

Originally Posted by RL18

Yeah the rears only, front have more than half tread. Considering how many rolling burnouts I do it’s impressive. Technically I could just buy new rears but I want to increase to 255/275 so I can get more traction.

There’s no argument when it comes to performance there’s a reason manufacturers do staggered setups on rwd cars. If your cheap you do square

I don't think you're getting as much traction as you think going from a 255 to a 275 rear. Tire compound would make a way bigger difference then size...

Staggered is all about looks, but that's just my opinion.

[Scubudo]

Well...I must admit that I am somewhat disappointed in that there was not more lively debate in regard to staggered vs square.

As requested, here is a picture of the rear tire wear pattern:
Micheline Pilot Sport 4S, 225/35R18 on 8 1/2" rims after 24,000 miles

[Tambohamilton]

225/35/18 is a weird size...what you running that for, especially on the rear?

[Scubudo]

Originally Posted by Tambohamilton

225/35/18 is a weird size...what you running that for, especially on the rear?

Sorry...typo. It should have read 255/35/R18

[Tambohamilton]

Makes sense.

Wear looks excellent. Wish mine would go as evenly as that!

[RL18]

Originally Posted by Scubudo

Well...I must admit that I am somewhat disappointed in that there was not more lively debate in regard to staggered vs square.

As requested, here is a picture of the rear tire wear pattern:
Micheline Pilot Sport 4S, 225/35R18 on 8 1/2" rims after 24,000 miles

Looks like good wear to me!

There’s no debate lol. If you want a cost effective solution go square, if you want all out performance go with staggered.

If staggering didn’t make a difference manufactures wouldn’t be doing it. It’s definitely not “just for looks”. By running staggered I can run more aggressive tires in the rear to enhance my traction. Compare stock 225/255 to a square 255 setup and you have more traction in the front, but less nimble than a 225 up front, and now you get oversteer because you have less grip in the rear. You could get more traction in the rear with a more aggressive tire in the staggered setup too. If you go 255/275 then you get more traction up front, then added traction in the rear over a 255 which will help counter any oversteer, having similar handling characteristics to the 225/255 setup but with added traction. Either staggered set up will be better then the 255 square set up. I run square A/T tires on my x5d because I don’t care about handling performance I just want a year round go anywhere tire that I can rotate easily.

[Scubudo]

How much oversteer would there be? I am not sure about most modern cars...but historically the vast number of cars not only square, but also had significant understeer.

Since the rear of the vehicle already tends to push out the right under hard straight-line acceleration (which may or may not be normal)...it would stand to reason that increasing front traction would augment such tendency.

Along the same lines of reasoning...wouldn't the DTC sense the loss of rear traction, causing it to try to intervene earlier...with braking and defueling? If that were the case, there should be significant differences in 0-60/qtr mile times between the 2 set-ups.
Has anyone attempted to quantitate such differences with the E90 platform?

Anyway...now I frustrated because I come searching for answers...and now have more questions...

[RL18]

Originally Posted by Scubudo

How much oversteer would there be? I am not sure about most modern cars...but historically the vast number of cars not only square, but also had significant understeer.

Since the rear of the vehicle already tends to push out the right under hard straight-line acceleration (which may or may not be normal)...it would stand to reason that increasing front traction would augment such tendency.

Along the same lines of reasoning...wouldn't the DTC sense the loss of rear traction, causing it to try to intervene earlier...with braking and defueling? If that were the case, there should be significant differences in 0-60/qtr mile times between the 2 set-ups.
Has anyone attempted to quantitate such differences with the E90 platform?

Anyway...now I frustrated because I come searching for answers...and now have more questions...

Why would you want oversteer on a rwd car? Maybe in a drifting set up. Oversteer happens when the front has more traction than the rear, so the rear end loses traction and will swing out. Of course traction control will kick in, but why do you want it to? You want the least amount of intervention with traction control. Understeer is when the rear has more traction than the front so the front tires are slipping and the rear is “pushing” it forward. Neither are desirable in excess, you want as close to balanced as possible (of course there are other factors and some people have preferences I suppose). Bmw did all this testing for you which is why they staggered the wheels. If it handled better with a square set up that’s what would be recommended.

To me the handling is perfect with a staggered set up. I’m on coilovers with m3 suspension though. The only time I ran square set up is in the winter 225s all around because the rear will “float”, but I don’t drive my 335d in the winter anymore.

Your issue most likely stems from your alignment that’s why I say you should get your alignment checked/done because it’ll tell you the most about why it might be doing what it’s doing so you can fix it or the alignment will fix it. I redid my entire suspension at about 115k, replaced every control arm, upgraded some things, inner and outer tie rods, and coilovers.

[Scubudo]

No...I don't want oversteer.

My point was that historically most vehicles have had square setups and understeer.

I admittedly can succumb to overthinking...so frequently get lost in the weeds trying to differentiate the theoretical/subtle from realistic/significant.

So I was hoping perhaps someone might have or be able to provide or point me to a source where someone managed to quantify such effects (particularly as it applies to the E90).

As for "thrust angle"...I did not even know that was a thing.
Given the even wear on the tires, I sort of doubted the answer for the tracking would be related to alignments...but guess I need to look into having that checked.

[RL18]

Originally Posted by Scubudo

No...I don't want oversteer.

My point was that historically most vehicles have had square setups and understeer.

I admittedly can succumb to overthinking...so frequently get lost in the weeds trying to differentiate the theoretical/subtle from realistic/significant.

So I was hoping perhaps someone might have or be able to provide or point me to a source where someone managed to quantify such effects (particularly as it applies to the E90).

As for "thrust angle"...I did not even know that was a thing.
Given the even wear on the tires, I sort of doubted the answer for the tracking would be related to alignments...but guess I need to look into having that checked.

Yeah just realize that bmw already did all this testing for you. It’s staggered because they found it handled the best. Rwd cars have more oversteer, since the driven wheels are in the rear. So minimizing the oversteer is what you want to do. By getting the most out of traction in the rear you will minimize the oversteer. I’ve never experienced understeer on my 335d.

The thrust angle is how your front and rear axles align. Think of those pickup trucks with shitty huge lifts that have the rear axle sticking out more on one side than the other. Ideally you want them to be parallel so zero or as close to zero as possible. On our cars the rest of your alignment will determine this, you can’t actually adjust your axles.

[Scubudo]

So...if you "can't actually adjust your axles" does that mean that thrust angle is not adjustable?

...and since BMW does sell the e90 with both square and staggered setup...that tells me little as far as how much difference I can expect if I switch to square. While I realize that the staggered setup was part of Sport and M3...there are multiple other differences between the various platforms, some of which I suspect offered little or no benefit (such as the rear spoiler, and cowel/strut brace).

[RL18]

Originally Posted by Scubudo

So...if you "can't actually adjust your axles" does that mean that thrust angle is not adjustable?

...and since BMW does sell the e90 with both square and staggered setup...that tells me little as far as how much difference I can expect if I switch to square. While I realize that the staggered setup was part of Sport and M3...there are multiple other differences between the various platforms, some of which I suspect offered little or no benefit (such as the rear spoiler, and cowel/strut brace).

Your thrust angle is dependent on the rest of your alignment, if your alignment is off your thrust angle will be off. Our differential doesn’t move its always aligned (bad mounts could make a slight difference), our control arms attaching to the subframe are the main factor in determining the thrust angle.

Try the square set up and see if you like it. Only you can determine which set up fits your needs the most. Me personally the way my 335d is set up (tuned, r90 pump, m3 suspension, and lowered on coilovers) I prefer to “promote” understeer because I don’t want the back end kicking out, especially with the amount of torque I have. Plus I want to be able to run an aggressive tire in the rear that gets me as much grip as possible in a straight line. If I had an lsd then it probably wouldn’t bother me that much having oversteer and maybe I would do a square setup but the “e-diff” we have is unpredictable, so I want it and the traction control to intervene as little as possible, which is why I like the staggered setup better.

[BB_cuda]

My setup is unique so hard to weigh in on the square vs stagger directly. FULL M3 setup including rear lower control arms, ground control coilovers, E92/E90 M3 sway bars, adjustable toe links, camber plates on front, and Wavetrac LSD.
I intentionally run -1.5 deg camber at all 4 corners for neutral feel. Running the twisties along Mississippi River levee road sure feels neutral to me. I run 33 psi on square 255/35/18 on Apex SM-10 18x9ET30. Putting on those forged wheels really woke up the handling too.
EDIT: the different rear lower control arms mean M3 rear shocks (horizontal mount screw through lower shock’s eye).

[BB_cuda]

Originally Posted by Tambohamilton

I'd put money on that being a flat spot on the tyre. Take the wheels off and check the tyres thoroughly.

Changed tires and noise disappeared. Tamo was right. I had thought flat spot was possible. I went to a taller sidewall with 255/40/18 square all around. A bit more cushy and fills the opening better.

[Scubudo]

In case anyone else has trouble with the rear end kicking out to the right on hard acceleration:
I installed aluminum rear subframe bushings and all of the rear bushings in the rear (other than the diff bushings). I also swapped the OEM swaybars to E93 M3 versions and did M3 control arm upgrades front and back at the same time.

While I can't say with certainty which part (or parts) fixed the problem, I would speculate that it had to be one or more of the rear bushings.

[Tambohamilton]

E91 M3?! Yes please!

I assume you mean e92 M3?