BMW 3-Series 2005 and earlier

burrsr

I have a theory on tire wear that has no grounds, it just sounds logical.

1) The near 50/50 weight distr certainly would induce more even wear.
2) The fronts are solely responsibly for directional changes, so I would expect wear patterns more latitudinal in nature -- perpendicular or diagonal to the tread.
3) Rears are solely responsible for propulsion, so I would expect wear patterns parallel to the tread.

Because of this, the wear happens to come out relatively the same (versus a front-driver where fronts have the burden of BOTH directional changes and propulsion). Also, due to the differences in wear patterns, BMW figures it's probably best NOT to rotate, keeping the tires on one duty for the duration of their lifetime -- rotating produces no lifetime benefits, and could potentially reduce handling characteristics. Why risk recommending to compromise one of the most satisfying aspects of the car?

I could be totally off-base on this, but it seemed to make sense to me

alpine325i

The old Kleen Wheels Dust Shields had the overheating problem and they took them off the market. The new Kleen Wheels have aero vents that force air into the front. I tested them trying to heat up the rotors. To my suprise, the Kleen Wheels cooled the brakes down even more than without them. I've been trying to convince everybody about how great they work. You won't know unless you try them yourself. )

shipo

Check out the Dodge 3500 with the 5.9L I6 Cummins engine vs. the Mopar 5.9L V8.

Diesel/Gas
HP: 245@2700/245@4000
TQ: 505@1600/345@3200

A very BIG difference, the Diesel is generating 505 pound feet of torque at 1600 RPM's, in some cars, that is just above idle!

Best Regards,
Shipo

brave1heart

No offense at all - c'mon. You helped me discover that there is a feminine side to my masculinity too - liking both the steel gray AND the steel blue - LOL...I guess Orient Blue is a nice neutral compromise and makes for a good average in my color preferences. Hmmm, maybe I should watch, was it "Will And Grace" and figure out more about myself. It's never too late, right?

brave1heart

Now, if we can only figure out how gearing works with HP and torque...
I still can't figure out how it is better to make torque at high rpm than at low rpm, because you can take advantage of gearing (e46fanatics' faq on HP and torque)

brave1heart

burrsr

Gearing is yet another topic that has always intrigued me. It is another optimization exercise that also requires fitting optimal gearing to the engine's torque curve to obtain maximum performance, fuel economy, etc. More variables this time, including torque curves, forward (and reverse) gear rations, final drive ratio, and even drive tire circumference.

It's hard to believe that only a few short years ago manufacturers were still fitting 3-speed autos to some engines. The Neon comes to mind -- talk about a mis-match of engine and tranny. Putting a 3-speed auto with a relatively high-revving, low-torque 4-banger optimizes nothing, except perhaps cost. I guess I've answered my own question there, huh?

JingleJill

When I took my car in for service this weekend, the dealer had a 325i on the lot. Topaz blue with sand leather. It was a beautiul car, however the sand leather was already filthy from people test driving the car. I agree that a gray interior is much better.

Stacy

platypus

Can anyone explain the technical benefits of the staggered wheel set-up on the 330i SP? The fronts are 17x17.5 (225/45/17) and the rears are 17x8.5 (245/40/17).

I have come across a good deal on a set of BMW OEM rims that are 17x8 all-around, fitted with 225/45/17 tires. What would be the pros/cons to altering my stock set-up?

burrsr

A couple of things come to mind:

1) Wider rears = greater contact area with pavement = better traction, especially on launches.

2) May make a difference to suspension calibration, but the profile affects this much more than the width.

brave1heart

Are they loud at interstate speed?

platypus

I thought I had read in a C&D article on the new M3 that wider rears contribute to understeer, which is undesirable for a sports car.

Any truth to this?

alpine325i

brave1heart and kominsky: To add midbass drivers to the HK you need: 1. A low voltage trigger interface- $50. 2. A 2 channel amp with at least 50 watts continuous power per channel- $150 to $300. 3. Any pair of 5 1/4" midbass drivers for the front doors. Boston Acoustics and MB Quart are pretty expensive, $260 to $400 a pair. The component sets cost more, but they have tweeters and the specific crossovers to achieve perfect balance of highs, mids, and lows. To keep the price down check out Kenwood, Rockford, etc... errickson: The system you described is called a one footprint system (1 amp powering the whole system). It would sound great but the ADS 336is's retail for $400 not $600, unless everything is more expensive where you live, it just doesn't sound right. The price of the amp, subwoofer, and install sounds about right. For the price of the install ($400) that should include the labor, the low voltage trigger interface, and the high power- low level cables and accessories. The ADS's are awesome, but at $600 a pair? I would shop around some more, look at some other component speakers that this place has to offer, unless you feel that the sound you heard coming from the ADS's are worth it. Demo alot of stuff between $300 and $600. Each speaker has it's own unique characteristics that defines and colors the overall sound. Some will sound bigger and smoother, some will sound really accurate but a little harsh. )

dhanley

Um, an automatic mustang has a 3-speed automatic. I had one as a rental. A horrid car.

dave

platypus

No problems with road noise. Just looking to personalize my car a bit, and the style 71s are very cool. (Depending on your tastes of course.) You would probably find them too busy.

brave1heart

I'm perfectly fine with oversteer. Oversteer is much better than understeer - you can just step on the gas Porsche-style and convert the overrsteer to understeer. If your car understeers, there's not much you can do other than braking or letting off the gas at least. The IS300 that I test-drove last fall had that severe understeer problem and I really didn't like it. I didn't know the M3 understeers.

platypus

Why is it then that C&D lauds a car for its neutral (WRX) to oversteer (E36 M3) characteristics and criticizes it for understeer (E46 M3)?

This subject was explained to me once using the following analogy:

- oversteer - you take a corner too fast and begin to lose it, you may hit stationary object (tree for example) with the rear of your car.

- understeer - you take a corner too fast and begin to lose it, you may hit stationary object (tree again) with the front of your car.

If this is accurate, wouldn't you want the collision to be with your rear/tail rather than your front-end??

lewparker1

I have an Orion 2 channel amp sitting in a shopping bag in my basement with a pair of MB Quart CS218s. Can I use the Orion amp with the trigger interface to power a new set of Quarts for the front doors (I don't think the 218s will fit in the 3er's doors)? Or do I have to get a new amp that is compatible with BMW's head unit? I hope I can use the Orion, I think I paid $400 for it about 10 years ago. It's been languishing ever since I sold my pickup truck about 6 years ago.

brave1heart

Thank you for the examples. I got confused for a minute above there so your examples make it much more clear for everyone (including me) what oversteer and understeer are. For me at least, oversteer is when the car steers more than what you would have expected for the steering input. Yep, the back end typically comes out when oversteer is severe (more common with short wheelbase cars). Conversely, understeer is when your are turning the wheel hard but the car just keeps going to the outside of the turn and would not stay on the course that you had intended. The '98 Porsche 911 that I drove once had a severe oversteer problem but as soon as you step on the gas in the turn, it corrects that and transfers it to neutral or even oversteer. It's a lot of fun. The IS300 would just not turn the wheels enough in turns to allow you to do anything with the power so your driving effort would often be reduced to letting off the gas. I know C&D praises neutral handling to oversteer - I can't see how understeer would be good for any race car. At any rate, for everyday driving at least, oversteer is preferable because it would allow you to control the car better; understeer is a lot more likely to send you off-road.

jnscheong

Double agent? No, my name is Bond, James Bond. :-) Just kidding.

My younger brother is looking into getting an A4 1.8T Quattro. I was just doing some checking around for him. Yes, he is well aware of this and other sites, but I am just an over protective older brother. :-)

jnscheong

burrsr

Both types of response occur at the limits of adhesion. Oversteer, as I understand it, is when the rear tires come around and effectively steer the car in an even greater angle than the front tires are pointed. And yes, applying gas in this situation will correct it, since acceleration sends more weight (and hence traction) to the rears. So, yes, the larger the rear tires relative to the fronts, the greater the likelihood of understeering, since the rears have more area and thus traction to keep it from oversteering.

brave1heart

I checked them at The Circle - these are the 5 double spokes, right? They look very aggressive and you are right that they would be too busy AND too aggressive for my taste and especially for a sedan. I still like them better than the 330i SP wheels, though. Are you getting the 18's?

brave1heart

From what I understand, the H-K money would be pretty much wasted because the H-K system is no help. Put it this way - you'd spend the same amount of money getting the midbass setup regardless of whether you went with the H-K. The only advantage of the H-K would be the subwoofers because you'd need to replace the front two speakers anyhow, correct? Please bear with me if I'm way off here - I'm clueless about stereos as you can see.

platypus

for the straight-forward technical response. It makes sense on the 911s that Porsche uses wider rears as those cars are notorious for oversteer.

However, I'm slightly confused by BMW's use of wider rears on the 330i SP and M3. It appears that they have taken it too far, giving the car a propensity for understeer. I wonder if a stock 3-series with the same size tires all-around under/over steers? Isn't the 325i SP set up like this? Thoughts brave? What about C&D's review of the 325i SP - what do they say?

kominsky

Most non-sports cars are tuned at the factory to default to under-steer in a corner. To a less experienced driver, it is easier to control that way. I've been playing around with the DSC off lately and believe me, even with the wider rear tires on the 330, over-steer is very easy to induce. A quick stab at the brakes followed by increased throttle or even letting off the gas a little and then getting back on it (trailing throttle over-steer) can cause the rear to step out. This is used as a steering technique by many (who's skills exceed my own). In an empty parking lot, I found how easy it is to spin it all the way around using these techniques... what a blast... there was smoke pouring from the rear tires. The first words out of my wifes mouth? "how much did you say it would cost to replace these tires?!" I told her that it was an educational experience and wouldn't be intentionally reproduced. ;-)

platypus

Yes, they are the bolted 5 double-spoke rims. Very sporty. Anyway, I haven't decided on them yet.

The other wheels I really like are the style 5s (bolted cross spoke composite wheel). These were the ones on the '98-'00 528i SP cars, and I think are still available on the '01 525i SP. (Pain in the !?* to clean though.)

Wouldn't 18s be excessive? It's my understanding that anything bigger than 17s on these cars is just for show, and could actually hinder performance.

brave1heart

burrsr - I don't think I'd agree that both types of response occur at the limits of adhesion. You don't need to be pushing a car to the limits of adhesion to feel under/oversteer.

plat - Don't remember off the top off my head what C&D says about the 325i's over/under but I can tell you how I feel about it. It has a slight oversteer which I really like because it makes the car more predictable and controllable. The oversteer can be turned into understeer relatively easy. I think the 245-wide tires on the 330i are impressive (if not too much to look at) but I seriously doubt that they improve handling a lot. The 325 and 330 are very similar (identical wheelbase) and I would expect that if the 325 handles great with all-around 225's, so should the 330. It is likely BMWNA added the 245's on the 330 to differentiate it better from the 325 but the end result is mixed. See, the M3 would need those 275's or whatever rears it is using for traction because of the significantly higher HP. At 107", though, the wheelbase may be a little too long for tires that fat and now that I understand your points better, I can see how it may result in understeer. In short, I'm perfectly happy with my 325's equal tire width all around and I'm guessing the 330 would be just as fine if not even better overall with 225's all-around.

errickson

Alp: Thanks very much for the information. It's easy enough to shop the price. Just wanted to be sure I was shopping price for a decent product!

Lewparker: If you are unable to use the amp you have in the shopping bag, I would encourage you to sell it on EBAY. You might be surprised at what that might be worth to someone. I have sold a couple of items I found while cleaning out the garage. The winning bidder paid MORE than what I paid for the items originally!!!

"One man's trash is another man's treasure" seems to be alive and well!

platypus

Given your example and the fact that I've yet to take a real driver's course, it's safe to say that the wider rears on my car are not adversely affecting its performance.

BTW, your comment on the DSC - how often do you drive with it on/off?

Same question to the others on this board...

brave1heart

Maybe that works better on the type of deer roads that you are driving on. I'm pushing my 325i VERY hard in corners and it grips like a champ w/o the DSC even attempting to kick in. Maybe the added HP in the 330 makes that easier I'd be guessing...

Hey, I love that parking lot "learning experience" if you can seriously call it that. You know that I park on the street, so often I have to make U-turns at the end of the street if I don't find a pkg spot. Having a RWD helps a lot in achieving that, especially in snow, and I'm really looking forward to that )

brave1heart

style 5 is pretty good-looking, i don't know...

18's definitely overkill. it hinders performance (too heavy) and slows down steering response. stick w/ 17's - sweet spot.

burrsr

I was driving my wife's minivan today (I know, I know -- dog duty. Our Basset sheds like a balding ape and therefore has limited exposure to Gretl) and noticed something I hadn't noticed before: the A/C button is a "snowflake" button! Seems as if the folks at Chrysler have plagiarized a page out of the Germans' HVAC book! And this was designed BEFORE the advent of Daimler-Chrysler!

burrsr

I agree that you can feel the onset of understeer or oversteer before it actually happens. In fact, I read an article by Patrick Bedard on why he prefers higher profile (relatively speaking) tires to ultra-low ones: the "feeling" period of the onset of these conditions is longer and smoother, whereas with ultra-low profiles, it is much more abrupt (although limits are higher).

But, by definition, any tire slippage (understeer or oversteer) occurs at the limits of adhesion. Otherwise, there is no slippage with adhesion.

brave1heart

Thanks - I didn't know that over/under is defined as tire slippage - I always thought (incorrectly) that is it just (over)reaction of the car to steering input while cornering.

Yeah, I love that article from Patrick Bedard that you are talking about. This guy has been racing all his life and knows what he's talking about. He gets a little monotonous but if you can get past his writing style, he is a wealth of knowledge. I remember him saying that "on-rails" handling is not necessarily better than higher profile tires that allow you to feel the slippage better before it occurs. However, I think he admitted that lower profile is marginally better on dry and wet roads but you give up a lot of handling in snow/ice. What I got out of it is that if you don't feel like swapping tires for the Winter, you'd be better-off with all-seasons for everyday driving and not giving up TOO much performance that way. Makes a lot of sense but I'd still take the low profile tires and suffer with them during the Winter OR put in snows if I can't take the pain. I guess it all comes down to driving style.

kominsky

I've only had it off a couple of times on the road. I have, however, been spending a decent amount of time in empty lots with it turned off. I've been driving low power, front-wheel-drive cars for many years and I've been trying to get a feel for what happens in different situations with different amounts of throttle/braking inputs because of the RWD. I'd like to do a couple driving schools this summer, but I don't want to show up without being mostly aware of how the car will react to my inputs (my understanding is that DSC gets turned off at the driving schools).

Like brave1heart, I prefer to drive on the safe side of the traction limits while on the road... never know when one of those big eight-point whitetails are gonna leap from behind a tree.
However, grabbing a big handful of throttle (sorry, motorcycling term) coming off of a corner does occasionally cause DSC to kick in.

brave1heart

Shipo - I thought these computer mouse guidelines might help you improve your computers. I got the instructions from a friend of mine. I wish the BMW manuals had instructions this good - enjoy

INSTRUCTIONS ON REPLACING MOUSE BALLS
> >> > >
> >> > >This memo is from an unnamed computer
> >> > >company. It went to all field engineers about a computer peripheral problem.
> >> > >The author of this memo was quite serious. The engineers rolled on the floor!
> >> > >Especially note the last sentence
> >> > >
> >> > >Mouse balls are now available as FRU (Field Replacement Unit).
> >> > >
> >> > >Therefore, if a mouse fails to operate or should it
> >> > >perform erratically, it may need a ball replacement.
> >> > >Because of the delicate nature of this
> >> > >procedure, replacement of mouse balls should only be
> >> > >attempted by properly trained personnel.
> >> > >
> >> > >Before proceeding, determine the type of mouse balls by
> >> > >examining the underside of the mouse. Domestic balls will be larger
> >> > >and harder than foreign balls.
> >> > >
> >> > >Ball removal procedures differ depending upon the
> >> > >manufacture of the mouse.
> >> > >
> >> > >Foreign balls can be replaced using the pop-off method.
> >> > >Domestic balls are replaced by using the twist-off method.
> >> > >
> >> > >Mouse balls are not usually static-sensitive. However,
> >> > >excessive handling can result in sudden discharge.
> >> > >
> >> > >Upon completion of ball replacement, the mouse may be
> >> > >used immediately. It is recommended each replacer have a pair of spare balls
> >> > >for maintaining optimum customer satisfaction.
> >> > >
> >> > >Any customer missing his balls should contact the local
> >> > >personnel in charge of removing and replacing these necessary items.

add123

Brave1heart,

Thanks for responding.

Den right,

It sounds to me like your are getting jerked around. Weren't you the one that was contemplating waiting for the 02 but decided not to?

add123

shipo

Believe it or not, it is my understanding that that is an actual memo from IBM from the mid 1980s. I guess at least one person at the "Itty Bitty Machine" Company has a sense of humor. ;-)

Best Regards,
Shipo

brave1heart

add123

Brave1heart,

Thanks for responding.

Den right,

It sounds to me like your are getting jerked around. Weren't you the one that was contemplating waiting for the 02 but decided not to?

add123

burrsr

I agree with your approach to winter/summer tires. We probably experience similar-severity winters here in Cinti as you do in Boston, maybe more freezing rain and less snow here. Based on that, I semi regret not getting the SP. I've already decided to get it on the next go-around. If I has to re-option today, I would select: SP, CD, sunroof, and xenon. The PP is nice, but not worth the cash; the same with leather. Step is neat technology, but yields a less intimate relationship with the car.

brave1heart

Couldn't agree more with the options. I'd only add in the heated seats and the trip computer. Hey, I was just talking to one of my colleagues who lived in Cleveland for long years. She's saying that Cleveland gets a lot more snow than Boston because of the lake effect but Cinti gets a little less snow and more freezing rain than Boston. It's really weird but we get a lot less snow right in Boston. The further you go out of Boston (within a 50-mile range at least), the more snow you get. Not sure how that works but it must be the ocean effect. In addition, I drive 95% city and highways and those are always cleaned up very well except in rare cases when we got too much snow too fast and in those cases you're better off staying home anyhow. I know that the summer tires perform better at higher temperatures and I'm not sure how colder temperatures would impact them but it can't be all that bad. I know everyone that I tell this to thinks I'm totally out of my mind but I am very comfortable driving in snow and I'm willing to give it a shot. I remember I drove from NYC to Boston once in at least 6-8 inches of snow on the highway all the way and it was a lot of fun. It was my FWD Jetta but I think I'll be OK with a RWD and electronic stability. If all else fails, the Tirerack's always open.

trejos28

brave1heart

veekay1

Thanks errickson!
I will check with my dealer whether: a.) the warranty is affected adversely by adding these and b.) whether the new generation "vented" Kleen Wheels do not cause rotor overheating, as Frank69 claims.
veekay1

dhanley

There's a simple reason most manufacturers dial in understeer.

Imagine you are cornering too fast--you are near the limits of adhesion. If your car understeers, your angle will lessen, and you will retreat from the limits of adhesion, and hopefully, the tires will hook up well. If you oversteer, your turn angle will increase, and you may well exceed the adhesion limits, and spin or slide out.

Generally speaking, 99% of the people are better off in situation #1--with understeer. I'm careful in the rain, myself, if i turn and punch it, the back wants to step out on me. I waited to get a BMW with a modern traction control.

Now, almost any car will understeer through turns in a lot of situations. If you can provoke enough oversteer to balance this, you can sail through most corners like a champ. I can kind of do this, but i do have DSC backing me up!

And, geez, slow down! I can't keep up with this topic!!

dave

aaron330i

But I stll want it now!

denk

Is the message# feature working or am I doing something wrong? When I punch in a number it takes me to a post that is some 300 posts away from the one I punched in.

brave1heart

That's if you manage to do it right but with the 3-series it should be fairly easy because of its perfect weight distribution. I will wait towards the end of my tires' life to do that on pavement but I only have to wait till the Winter for snow and that should be just as much fun. Problem is, I might be doing a lot of this even when I don't want to or even expect it but well, we'll find out if I'll live :0)

brave1heart

"today i am 59, next year i'll be 60. yesterday, i was 22. don't wake up at 60 and wish you had today to
do over."

-muhammad ali