[Neema]

Just got back from driving to Newport real quick and I took my sisters bone stock E90 325i. I noticed that her car's steering response is sharper and more refined then mine. She has little to no play in her wheel. The car remained very flat and stiff through corners as well. She has no sports pkg, and is on 16's or 17's (inch wheels) I believe. Her brakes even felt a tad bit more firm and planted then mine.

I know that my 20'' wheels with little, yet wide rubber and my H&R/Koni Sport combo attribute to my harsher ride, so Im not going to mention that her ride was much much smoother, obviously. I've been in 2 minor accidents, both of which did NO damage to the frame or anything structural at all.

So why is there so much more play in my steering wheel, and sometimes I almost feel like I have to actually try to keep my car going in a straight line versus my sister's car that was effortless? Why does my car feel like it looses traction and very slightly jolts to the left or right when I go over a thick sewer cap or bump while I'm driving down a long sweeping turn at a decent speed, like a fast on ramp for example? And why does my car's cornering ability seem to be only slightly better then my sisters car? And why do my brakes feel mushier? And why does my car roll during corners more then my sister's car? Haha, I know Im asking a lot of questions, but I just cant quite put my finger on it.

So whats the deal guys? My brake fluid is almost at the minimum marking, and my pads have been switched to the low dust ones, but the overall performance didnt change too much over stock with those pads.....so I dont know. And I have after market springs and matched Koni shocks, with sport pkg, wider rubber, a lower center of gravity, and larger + more powerful brakes. Yet they all seem to perform worse then my sister's car, a bone stock E90 325i.

Now, I have a questions about my sister's E90. Why is the road noise and braking noise so much louder in her car? In last few feet before coming to a complete stop, there is a sound that is like a mix between a metal grinding noise and a "WHhhhhooooooo" sound as you come to a stop? And even while cruising, her tires are annoyingly loud. You can't hear anything when I apply my brakes, no matter what speed, and my tires are almost dead silent. My cabin is quiet, while her is filled with all that road noise. Why is this?

I'd really appreciate some insight on all these questions and thank you for taking the time to read and reply!

[garyhgaryh]

Perhaps she doesn't abuse her car like you do yours?

[BMW DIET]

Originally Posted by garyhgaryh

Perhaps she doesn't abuse her car like you do yours?

point point

[Neema]

haha, no come on.........for real man.

[j|rz44]

werent you in 2 accidents already?
may be that, no?

[garyhgaryh]

that definately could play a big role in how your car feels. I've driven cars that have been in accidents and they didn't feel quite right - just can't put a finger on what's wrong with it. I driven a car 10 years old that has been owned by the original owner and never been in an accident and it drives like a new car (or better than a two year old car that has been in an accident).

[Comet]

road noise: she probably has trash tyres

brakes: her brakes aren't as faded as yours maybe?
swerving: get yourself aligned
grip: get new, better tyres

bottom line: after market doesn't necessarily mean better

[E92Fan]

Can't possibly comment on what all the differences are, but here are some thoughts:

1) You have much wider, bigger wheels on your car, front & back, with a resultant increase in contact pitch (more tyre on the ground). The wider wheels at the front especially will lead to much greater tramlining - ie. the car will following grooves and ruts in the road much more than smaller less harsh wheels, therefore making the car wander around a lot more and feel less stable in a straight line. If the road was perfectly smooth and flat, with no camber or ruts, then your car would be much better.

2) You feel your car is being deflected off line when going round corners - yes, this almost certainly down to the fact your car is lower and stiffer. On a race track, the lower/stiffer combo is massively better as there will be more grip and less roll - this is only because a race track is smooth and grippy however. On normal roads, you find ruts, bumps, off-camber slots - and a car with low suspension compliance will not absorb the bumps as well, and so your car will feel as though it is skipping or bouncing round the corner. In short, on your average road, your sister's car may well corner faster because it is more compliant over bumps, and can therefore carry more speed.

Basically, you've discovered one of the limitations of having a lowered/stiff/big wheel combo car which wasn't originally setup like that - unless the new setup is perfectly customised to your car (which it won't be unless you have specific coilovers etc etc) you will always have a compromised vehicle on normal roads. It's only when you get to the smooth, open roads of really good highways, or on the track, that you will notice the difference in handling.

3) Why does your car roll more? I don't know - subjective feeling perhaps?

4) Brakes? You've hammered yours and you've boiled the fluid? Again, don't know buddy

5) Braking noise on your sister's car - maybe the brake pad wear sensors are protruding too much are grinding against the disc? Maybe there's stone stuck in the caliper?

6) Tyre noise - maybe your sister's car has particularly noisy tyres, and yours doesn't? How long's a piece of string??

[Neema]

Originally Posted by E92Fan

Can't possibly comment on what all the differences are, but here are some thoughts:

1) You have much wider, bigger wheels on your car, front & back, with a resultant increase in contact pitch (more tyre on the ground). The wider wheels at the front especially will lead to much greater tramlining - ie. the car will following grooves and ruts in the road much more than smaller less harsh wheels, therefore making the car wander around a lot more and feel less stable in a straight line. If the road was perfectly smooth and flat, with no camber or ruts, then your car would be much better.

2) You feel your car is being deflected off line when going round corners - yes, this almost certainly down to the fact your car is lower and stiffer. On a race track, the lower/stiffer combo is massively better as there will be more grip and less roll - this is only because a race track is smooth and grippy however. On normal roads, you find ruts, bumps, off-camber slots - and a car with low suspension compliance will not absorb the bumps as well, and so your car will feel as though it is skipping or bouncing round the corner. In short, on your average road, your sister's car may well corner faster because it is more compliant over bumps, and can therefore carry more speed.

Basically, you've discovered one of the limitations of having a lowered/stiff/big wheel combo car which wasn't originally setup like that - unless the new setup is perfectly customised to your car (which it won't be unless you have specific coilovers etc etc) you will always have a compromised vehicle on normal roads. It's only when you get to the smooth, open roads of really good highways, or on the track, that you will notice the difference in handling.

3) Why does your car roll more? I don't know - subjective feeling perhaps?

4) Brakes? You've hammered yours and you've boiled the fluid? Again, don't know buddy

5) Braking noise on your sister's car - maybe the brake pad wear sensors are protruding too much are grinding against the disc? Maybe there's stone stuck in the caliper?

6) Tyre noise - maybe your sister's car has particularly noisy tyres, and yours doesn't? How long's a piece of string??

GENIUS!!

Great response man, thanks so much. You cleared up so much for me. Not so much with the road noise being attributed to the type of tires, because I just wanted to make sure that there weren't other variables possible, otherwise I knew that. But with the explanation of terms like "Tramlining," or "Camber slots," you really cleared many things up for me. And explaining the dynamics of a race track and stiff/low suspensions versus street use and a stiff/low suspension, was also great.

Thanks again

[Neema]

Now I have a viable and clear answer as to why my steering felt difficult to maintain in a straight line. Tramlining.

[E92Fan]

In terms of road noise, the two main reasons for tyre noise coming through are firstly the tyres themselves (inherent design, tread depth remaining, health of the tyre), or secondly a compromised suspension (bushes, collapsed damper, broken spring) which would transmit noise through the components.

However, you should be able to notice if the suspension is compromised, as it would be noisy/uncomposed over bumps/ruts and the handling will be distinctly variable.

[TheAcAvenger]

E92fan hit the nail on the coffin. Anyone will tell you that when it comes to handling, steering, and response, your wheel and tire combination is the most important mod of them all.

[jaaz]

If her 325i is running run-flats, that would contribute to the louder road noise.

I hear you on the comfortable ride. I'm driving around my non-sport package 335i sedan while I wait for my new suspension to arrive, and let me tell you, it sure is easy to get used to the comfortable ride when you're just driving to and from work. But the minute you drive the car aggressively around a turn, you notice the floaty-ness of the car. It's like life I suppose, everything's a compromise.

This was part of the reason I decide to stick with BMW OEM (Performance Suspension and Wheels/Tires) in upgrading my suspension since BMW "claims" it is an acceptable compromise between performance and comfort. We'll see.

[Neema]

Originally Posted by TheAcAvenger

E92fan hit the nail on the coffin. Anyone will tell you that when it comes to handling, steering, and response, your wheel and tire combination is the most important mod of them all.

really?! I thought that the actual suspension its self came first. I mean of course , I knew that light weight, moderately sized wheels (in terms of diameter) made a difference in the acceleration and nimbleness of the car. But I didnt know that they were that influential on the car's handling dynamics.

Alot of times I really do wish I just went with a set of Morr Alloy VS8's or something.....and I love the concavity look versus lipped wheels. But I just couldn't get over the fact that they only came in a 9.5 width.

I think that one of the MAJOR aesthetic draw backs of the E92 is its lack of fender flare, or arch in the rear. And it is especially evident with lipped wheels. I think cars that have less aggressive fenders and run relatively narrow wheels (narrow meaning 11-11.5'' and bellow), look better with concave wheels. Thats probably why you can get away with a great looking CSL rep on an E92, but not so much so with every lipped wheel out there.

Im rambling on now, and I need to stop hah. Basically..... I should have got a set of lighter weight, smaller, and concave wheels...like the Neez QD7 or Morr VS8.

[Neema]

Originally Posted by jaaz

If her 325i is running run-flats, that would contribute to the louder road noise.

I hear you on the comfortable ride. I'm driving around my non-sport package 335i sedan while I wait for my new suspension to arrive, and let me tell you, it sure is easy to get used to the comfortable ride when you're just driving to and from work. But the minute you drive the car aggressively around a turn, you notice the floaty-ness of the car. It's like life I suppose, everything's a compromise.

This was part of the reason I decide to stick with BMW OEM (Performance Suspension and Wheels/Tires) in upgrading my suspension since BMW "claims" it is an acceptable compromise between performance and comfort. We'll see.

I hear you on that too!!! I miss being comfortable in a car haha.

[Chowbow]

I'd say the 20's aren't helping, and depending on the tires that you're running, that may make a huge difference.

What H&R springs are you running? The H&R race springs are really short, and I'm more than willing to bet that during compression, the car is smashing into the bump stops and actually riding on bumpstops. H&R sport springs should be better though, although it could still happen, you'll have to check.

The alignment on the cars can make a huge difference. Since her car is at stock height she has the advantage of the suspension geometry working exactly as it should (castor and negative camber changes etc.). Make sure your alignment is done well, especially after your accidents.

Could be a huge number of things but a car with aftermarket parts on the car doesn't necessarily handle better than a stock car. Often times people will just dump money into their cars and bought parts that actually make their car perform worse... And if not set up correctly, then the car will handle badly as well.

[bsamoul]

she has the 16" turanza el42's which were recalled for that very issue.

[sg335]

Her motor is lighter and therefore less weight on the front end so better turn in and quicker steering.

[luca335i]

2O Inch wheels may contribute to more understeer, which would make the 325 easier to turn. Maybe go with a set of KW coilovers so you can adjust ride height and dampening. Then get yer car corner balanced .

[Neema]

Originally Posted by bsamoul

she has the 16" turanza el42's which were recalled for that very issue.

Is this something that can be claimed at a dealership and have done by them at no charge, since these tires are OEM spec, and now they've been recalled. So would I be able to present them with the fact that her tires where recalled, and that thats what BMW originally put on the car, so now that those are faulty, they need to be replaced under warranty?

[Neema]

Actually, I drove around today and noticed that though my ride was harsher, I can definitely turn harder, faster, and more precise then hers. Yet the brakes still feel a tad bit soft. So really, its only the slight tramlining caused by my wider front wheels that makes the biggest difference between her steering feel and mine.

[Luongo]

My 330i non-sport originally had the piece-of-shit 17" Bridgestone Turanza tires that started making humming noise like crazy when braking.

Ever since I replaced them with Continentals, the ride has been butter smooth.

BTW, I had to pay 50% of the tire parts and no labor as my car had around 20,000 miles when I got the replacement tires.