[TheAcAvenger]

I was thinking about which sway bars to get, and since Harold@HP is out of town, I decided to search for myself and I realized how many options and how many reviews there were. I'm going to go ahead and compile them here tonight and tomorrow via the threads on e90post. But if you have any experiences or want to chime about which are the best or best value, write it up.

This thread can be well supplemented by Mr 5's:
http://www.e90post.com/forums/showthread.php?t=169116

Hotchkis vs. UUC vs. H&R vs. M3 vs. BMW Performance

Hotchkis
- Front sway: 1 1/4" (32mm) tubular steel (95% stiffer than stock)
- Rear sway: 5/8" (16mm) tubular steel (105% stiffer than stock)
- Polyeurethane bushings, adjustable end links
-$450

M3
- Front sway: 26.5mm tubular steel
- Rear sway: 23mm tubular steel
- Comes with bushings, bushing brackets, reuse end links
- $370-450 MSRP

H&R
- Front sway: 27mm "strongest and most durable steel allow (50crV)
- Rear sway: 20mm
- Urethane/Teflon composite bushings
- $475

UUC
- Front Sway: 28mm 3 hole adjustable
- Rear Sway: 19 mm 2 hole adjustable
- Polyeurethane bushings, Adjustable front end links, rear stops provided
- $465-500 MSRP

[TheAcAvenger]

Reviewer: "who's ur daddy?"
Car: 323xi
Simultaneous mods: KW V3/UUC

Post:http://www.e90post.com/forums/showthread.php?t=306107

"I took the xi to the track before and all I can say is that the suspension is pretty soft. The transitions between corners was really unsettling to the car and thus to the driver. On the street, the word I would ascribe to the stock suspension is "sloppy". Way too much body roll.

With the KW V3's and UUC sways, the car just corners on rails. Really flat. Just fun fun fun. Over bumps, the car seems just a tad more stiff, but surprisingly it just seems so much more controlled - more solid. Not sure if it's the rebound setting. I might tweak it a little softer, but not much more so.

I never understood why people would swap out suspensions - thought it was a terrible waste of money. But the unsettling body roll made me look at this option. I now totally understand why people re-do their suspensions..."




Reviewer: ucdbiendog
Car: E90 335xi
Simultaneous Mods: UUC Sways, front and rear

Post: http://www.e90post.com/forums/showthread.php?t=275034

"So this weekend I (finally) got to install the front/rear sway bars on my 335xi. They have been sitting in my garage for about two months now, so Iwas very excited to do this. In terms of installation, it was not too bad. My dad and I did both front and rear in about 4.5 hours. To me, it seemed like the front was slightly more difficult. There are a couple hoses in the front that need to be detached and moved out of the way to be able to drop the stock sway bar, and on one of these hoses there is a bolt further up in the engine bay that is very tricky to remove.

Now I haven't really had a chance to take it on an extended drive in the twisties, but here is my first impression. I can definitely notice a reduction in body roll while turning which is really nice with the AWD. The car is more responsive to steering inputs, but not the point that it feels jumpy. I put the rear bars in at their stiffest setting, and now the car feels more neutral as opposed to understeer with the stock bars.

In answer to one of my previous questions, the adjustable end links that came were indeed replacements for the front end-links. The stock ones were vey light weight (likely aluminum) and the new ones were much beefier (stainless steel).

All in all, it was very worth the cost, and it was a great father-son project for fathers day weekend. Cheers!"

Relevant Post from "cyphr": The front is non-adjustable, the rear is adjustable. The noise from the bushings can be eliminated using marine grease (I use Amsoil purple marine grease)



Reviewer: "jbass524"
Car: E92 335i

Post: http://www.e90post.com/forums/showpo...27&postcount=4

"I have UUCs and would not recommend them at all. They are far too stiff for the car limiting the BMW-engineered mechanical grip the car likes. OVERKILL. They're huge bars but bigger is not better.

UUC will tell you how they get rid of understeer and make turn in sharper. This is correct to a degree. Once you start driving fast the loss of the BMW-engineered grip starts rearing it's head.

No matter what the performance gains or losses might be they have consistently loosened up and cause a lot of noise. Not worth it.

You should definitely look at getting the M3 bars. but don't look at sways as a big upgrade. If you can, work on other areas of the suspension then put sways on last. And definitely have someone spec and install suspension that has a lot of experience."



Reviewer: "longdoj"
Car: 335xi
First: Rears, Later: Fronts

Ugh I keep forgetting to get the tech specs from Rob and he's out for the rest of the weekend. Someone PM me or something on Monday and I'll find out.

So...Oh...My...God....this bar is fantastic. When I got the rear bar in, the stock pile of donkey crap Toyota like thing that had a 335xi on the back of it became a Bimmer. Not necessarily an E36 M3 like Bimmer, but a Bimmer nonetheless. When going around turns (with nannies off) you could glide the car into an oversteer situation with the tactile response of the front of the car twisting. So, with the remaining body roll, you could tell how to "let" the back out gently. With the front bar we've moved up to M Coupe type rigidity.

There's that circle in front of my school I use to give me quick feedback on changes to my car. Well usually I go around the first S and then sort of throttle steer around the sweeping left into a straight. Well this time I was trying to kick the rear end out and was going faster and faster and faster and the damn car wouldn't turn over until finally I felt the tires quickly start losing grip and I corrected. That is to say, there's no longer the tactile feedback of the car twisting because....it DOESN'T AT ALL! Literally it was as if I was going in a straight line. Oh...and this is on my garbage stock Continentals with my garbage stock wheels....I haven't even tried the car with my K1/RE01R combo yet.

Speaking of straight lines, with just the rear bar installed there is a strange feeling changing lanes at high speeds. Not bad, not good...just strange. It's kind of as if you were asking the car nicely to move over a few feet and it was being a baby about it. With the front bar installed the car remains planted at all times and leads to much more confidence at high speeds. Changing lanes feels natural. The car obeys your every command willingly.

Also, the bar really didn't contribute a noticeable level of understeer. I mean, I suppose that it changes the steady state oversteer to limit traction imbalance oversteer. However, in steady state the car is tremendously balanced. I would HIGHLY recommend this to any XI owner that gives a damn about corners.

[eltoshan]

For those who have tried more than 1 front sway bar, which one is the most stiff? I would assume that it would be the Hotchkis, am I wrong?

[TheAcAvenger]

Originally Posted by eltoshan

For those who have tried more than 1 front sway bar, which one is the most stiff? I would assume that it would be the Hotchkis, am I wrong?

From reading about 10 or so threads so far, the H&R rear actually seems to have the most dramatic affect. IIRC, hotchkis were recommended for a car with an LSD, whereas the M3's were recommended for a car without it.

After reading the other sway bar discussion thread from 2008, I get the feeling that anything deviating too far from stock has the potential for adverse handling consequences. However, the hotchkis tube is hollow, so it's size might not have as much of an impact as one might think.

[TheAcAvenger]

leftcoastman:

First off, my TC Kline system is bouncy on the surface streets but BETTER THAN STOCK on the freeway.

This is with stock wheels and tires. On the track with my track tires/wheels, it is no comparison.

My take is that with the E90/92, anti-swaybars are good for STREET use. It makes the car feel flatter, which some may think is better.

But if you ever go on track, you will be cursing a thicker rear anti-swaybar from the first session to the end of the day. With it, I was experiencing very very very bad wheelspin in corners. We're talking hitting the rev limiter if I even thought about accelerating before I was straight. Additionally, it made the car snap oversteer on occasion.

The thing I really like about the E90/92 is that it's very predictable. Slow, easy rotations. The thicker rear anti-sway would make me gripgripgrip...SNAP! FWIW - my laptimes were slower with the thicker rear anti-sway, I surmise because I couldn't accelerate worth crap out of corners.

$500 to install the anti-swaybars. $500 to remove the anti-swaybars. $1000 wasted.

If you're just going to street it, then it might work. Many like that "feeling" of less roll.

.......

Sorry if I wasn't clear.

Regardless of what you do in front, the rear bar will effectively make the rear end more like a solid rear axle (that's what antisways do).

If you just do a rear anti-swaybar, you will get tons of wheelspin.

You can put a 1,000 mm bar up front, as long as you thickened your rear anti-sway, you will still get tons of wheelspin.

stressdoc

IMO the H&R sway bars are not a good idea. Some like the "feel," but the rear bar is waaaay stiffer than OEM and will produce some undesirable characteristics, such as the snap-oversteer and inside wheel lifting that leftcoast notes.

If you are going to track your car and you know how to tune a suspension then the UUC or Hotchkis options, combined with coilovers, are a great way to go, especially if you have a LSD.

If you will be tuning your car primarily for the street, then the BMW M-sport rear sway (14mm) is a good swap for the ZSP (13mm). I would do this in combo with either the BMW performance suspension package or coilovers.

I would strongly advise against the H&R sways, and the fad to lower your car with H&R or other springs. Believe me, you are f#%ing up your suspension. Thicker, bigger, lower does not always mean better, especially for street conditions where you need compliance. Look at what the Euro tuners -- Alpina, ACS, et al -- are doing: no more than 1cm lowering, slight increase in rear sway, even slighter to front, better dampers, but not stiffer springs.

harold

We are currently using the Hotchkis front anti-roll bar only and using for very fine tuning of the handling of our project 335i.

Most of our suspension tuing is done with spring rates and damper settings. We only added the Hotchkis front anti-roll bar to reduce front body roll and lessen the effect of roll induced camber changes, thus keeping us from running more than -3 degrees of front camber. The end result is much less understeer.


The increase in roll stiffness up front is barely noticeable after the installation, probably because of our particular suspension combination. Ride qualty did not change by adding the Hotchkis front anti-roll bar.

Harold

[TheAcAvenger]

Reviewer: Quisp
Car: 2007 335i
Simult. Mods: Koni FSD, Eibach Pros, Hotckis front and rear

Post: http://www.e90post.com/forums/showpo...8&postcount=92

"I went with the Hotchkis Sway bars front and rear, also the Koni FSD and Eibach Pro Kit and I am very happy with it. I had it all installed at once so I cant really say how much each compnoent added to the handling, but from what i have read it seems the sawy bars help handling more than shocks and srpings, which do more for the ride. That is not to say the shocks and springs dont do anything for handling, they help a lot. I chose the Hotchkis because they were lighter and I read that the H&R was better suited for harder driving than I usually do. I also saw something about the iside wheel coming up in very aggressive turns.
The hotchkis are not adjustable though. As for the install, it looked like a pain in the ass and I left that up to a local garage that works on a lot of BMWs.
The setup i got is very nice for me. I like to drive the country roads and truns fast and hard, but i dont track. I also wanted a comfortable ride as it is my daily driver. I was able to get a good balance with this and it actually rides better than stock. A lot less understeer and body roll plus the car feels much more grounded. To me it used to drive like it was skimming the surface of the road and not really planted. Now it feels planted and gives more confidence when i drive it.
The car holds straight lines better at highway speeds. Less steering correction needed, not as twitchy.
Where i used to feel every seam and crack in the highway I dont anymore. The bumps diminish but the dips are a bit more exagerated. The bumpy turns are better than stock but the car still skips a bit if the turn is especially bumpy and I am going a bit faster. There is barely any front end plow or dive from the front end when I am in a changing radius turn and have to tighten it in the middle. Prior the car would feel like the nose was going to the ground and then the front tires would start to come loose.
I realize I am a bit late with this info but I hope it helps."



From "Mwahlert"

"i received this "sales pitch" from hotchkis a few months ago when i was shopping sways.

"E92 BMW Sway Bar Development Theory

For the ultimate street-track handling, bigger isn't always better. A balanced, tuned sway bar system is!

The Final Result:
The BMW E92 is a great car with loads of turbo induced horsepower. However, it's a somewhat heavy car at 3590 lbs, and in stock form has significant body roll during cornering. Unlike the new M3 with 50/50 F&R weight distribution, the E92 has 51% front weight bias. Therefore, we chose to aggressively increase the front sway bar rate (95% stiffer than stock) to reduce much of the body roll and dramatically quicken steering response. We increased the rear sway bar rate to 90% stiffer than stock to reduce roll, but not to harm corner exit traction.

Our Methods:

We equipped our BMW 335 ci development car with Bilstein PSS10 Coil-overs, Bridgestone Potenza RE01R and RE050A tires (from The Tire Rack) and a Stop Tech big brake upgrade package. Then we spent numerous hours testing to develop our balanced sway bar system worthy of definitive handling improvements on the street and track.

We tested 4 rear sway bar sizes, and two fronts to determine the proper roll stiffness and roll couple. We put these combinations through our battery of punishing tests including 600 ft slalom and numerous trips to our local SCCA and BMW CCA autocross events. We finally decided that the 1 ¼” (32mm) front and 5/8” (16mm) rear combination gave the E92 the best balanced, most comfortable handling on the street and track.

We tested the larger 0.75" (20mm) solid rear bar (355% stiffer than stock) with negative results. The BMW makes boost quickly and when the turbos spooled up the rear tires would easily break traction and our forward bite would suffer. We knew our BMW could post quicker lap times with faster corner exit speeds. This meant tuning the rear sway bar to help get the power to the ground early as possible. After we reduced the rate to 105% stiffer than stock, we were able to apply the throttle earlier, have much quicker corner exit speeds and ultimately achieve faster lap times.

We know these results to be true from past experiences developing sway bars for the 500 hp 2007 ZO6 Corvette. With the ZO6, we achieved the fastest lap times using a rear sway bar that was 15% softer than stock. Absolutely contrary to what most people think!

For the ultimate street- track handling, bigger isn't always better. A balanced, tuned system is!"

[TheAcAvenger]

Mr. 5

I installed the 14mm sway bar, and I now know what Leftcoastman is talking about. I rounded a corner, hit the gas, and my tires were more likely to spin.
I'm not complaining though. I really like the feel and I think that it's the perfect size for the regular 335s.

I'm glad I didn't go with the 15mm XI sway because if I can feel the tires spinning a bit with this one, I could just imagine what would have happened with the 15mm.

For those who are thinking about the M3 20mm bar, I would highly encourage you not to get it, unless you like going through tires really fast and doing 180s around corners. That is, if you drive spirited like myself.
Do not start comparing our suspension with the M3's suspension because it is completely different. Yes, the M3 has a 20mm sway that is fit for the M3's suspension.

......

OK guys,
I've added another variable into the mix.
I ordered the front Hotchkis bar to go along with my 14mm rear M sport bar.

Since Orb was kind enough to post about the different percentages, I'd like to add my setup to the mix.
I'm going to have the following:

Front
Hotchkis-31.75 mm: 75961 mm^4

Rear
M-sport-14.0 mm: 3771 mm^4

Front/Rear Biasing

Hotchkis front + M sport rear: 95% / 5%

......

I can easily say that I think I screwed up, but I will tell for sure after I do the install.
If you look earlier in the thread, I was looking at installing the set but there was worry about the improper balance, bla bla.
I was also worried about installing a rear sway bar that was too stiff, so I stuck with the M sport.
I didn't want to be loosing the rear end around the corners which is what a thick rear sway will make you do.
Although I agree with you, it looks like H&R just came up with some "arbitrary diameters and threw them onto market."
The reason why I say this is because the rear bar just seems to be way too thick for this car, especially when comparing to the front H&R bar.

......

Ok, I edited my post to clarify my statement.
I understand what you are saying but my car feels extremely good on the track, and honestly, for having the ability to drive my family around comfortably and also be able to have the feeling as I do on the track, then I'm completely happy.

Sometimes, having the ultimate track car is not the most important thing for everyone.
After I installed the front M3 links, I had more of a problem with oversteer than understeer, and the oversteer problem was hardly anything.

For myself, I have acheived my ultimate setup for both daily driving and the track.

I have the following:

Sport springs
M sport rear bar (14mm)
BMW Performance Dampers
M3 strut links and wishbone links
M3 strut brace

I will never change my springs because I am happy with the ride height and the ride quality.

[eltoshan]

Originally Posted by TheAcAvenger

From reading about 10 or so threads so far, the H&R rear actually seems to have the most dramatic affect. IIRC, hotchkis were recommended for a car with an LSD, whereas the M3's were recommended for a car without it.

After reading the other sway bar discussion thread from 2008, I get the feeling that anything deviating too far from stock has the potential for adverse handling consequences. However, the hotchkis tube is hollow, so it's size might not have as much of an impact as one might think.

Thanks for the response, but that's not quite what I'm looking for. I basically need to know which of the front sway bars available is the stiffest, for SCCA stock class autocross I pretty much need as little body roll as possible. On another thread I found the second moment of area for the different bars, but that's really only one aspect torsional stiffness.

[TSM330i]

I've had the UUC on for more than 1-year with 6 track days and quite a bit of daily commute.
They work perfectly and flawlessly. I've had no issues at all with my suspension (JIC Cross coil-overs included). My suspension is tailored to slight understeer (read-safe). The amount of grip is immense. On the track running street tires (Goodyear F1 Asymmetrics) I pulled 1.06g turning left and 1.08g turning right. The car is completely flat in the turns and is really predictable.

[bavarian19]

interesting read

[bavarian19]

what about BMW Performance front sway?

[ucdbiendog]

I was gonna post my review but it looks like Avenger already used the search key and linked it.

[Alpina_B3_Lux]

Originally Posted by TheAcAvenger

I was thinking about which sway bars to get, and since Harold@HP is out of town, I decided to search for myself and I realized how many options and how many reviews there were. I'm going to go ahead and compile them here tonight and tomorrow via the threads on e90post. But if you have any experiences or want to chime about which are the best or best value, write it up.

This thread can be well supplemented by Mr 5's:
http://www.e90post.com/forums/showthread.php?t=169116

Hotchkis vs. UUC vs. H&R vs. M3 vs. BMW Performance

Hotchkis
- Front sway: 1 1/4" (32mm) tubular steel (95% stiffer than stock)
- Rear sway: 5/8" (16mm) tubular steel (105% stiffer than stock)
- Polyeurethane bushings, adjustable end links
-$450

M3
- Front sway: 26.5mm tubular steel
- Rear sway: 23mm tubular steel
- Comes with bushings, bushing brackets, reuse end links
- $370-450 MSRP

H&R
- Front sway: 27mm "strongest and most durable steel allow (50crV)
- Rear sway: 20mm
- Urethane/Teflon composite bushings
- $475

UUC
- Front Sway: 28mm 3 hole adjustable
- Rear Sway: 19 mm 2 hole adjustable
- Polyeurethane bushings, Adjustable front end links, rear stops provided
- $465-500 MSRP

In the UK section, E92fan has written an excellent review of the Hartge sway bars / anti roll bars: http://www.e90post.com/forums/showthread.php?t=101524

Alpina_B3_Lux

[flux]

I have eibach sway bars. Basically it's amazing.
Anybody that has driven with me knows that my car stays flat.
Although sways bars are a difference, the eibach springs and Koni yellows are great too.
Eibachs are recommended by me. Highly!

[jbass524]

Originally Posted by eltoshan

Thanks for the response, but that's not quite what I'm looking for. I basically need to know which of the front sway bars available is the stiffest, for SCCA stock class autocross I pretty much need as little body roll as possible. On another thread I found the second moment of area for the different bars, but that's really only one aspect torsional stiffness.

Not sure if you're trying to comply with class rules but try to do most of your roll tuning with the springs then fine tune with sways.

If you put stiff sways you may have a flatter car but would probably create more of whatever negative handling characteristic you have. This becomes evident when you are pushing above 90%. The warm up lap feels amazing but then you can't understand why you're running slower times when you start pushing:

1. Live axle effect and inside wheel running lighter in turns.
2. increased spring rates by putting on a stiff bar and you don't have the dampening to work with the stiffer springs, so to speak.

This was my experience and my opinion only.

[eltoshan]

Originally Posted by jbass524

Not sure if you're trying to comply with class rules but try to do most of your roll tuning with the springs then fine tune with sways.

If you put stiff sways you may have a flatter car but would probably create more of whatever negative handling characteristic you have. This becomes evident when you are pushing above 90%. The warm up lap feels amazing but then you can't understand why you're running slower times when you start pushing:

1. Live axle effect and inside wheel running lighter in turns.
2. increased spring rates by putting on a stiff bar and you don't have the dampening to work with the stiffer springs, so to speak.

This was my experience and my opinion only.

No spring changes are allowed in stock class, so we need to make the most out of it with super large front sway bars and stiff shocks to keep the camber during sweepers. Camber and tires are by far the 335i's biggest weakness in stock class.

I actually might just do an STU build, and leave the r-comps and hardcore autocrossing to the SM 2G DSM that I'll hopefully be pickup.

[Gen_E92]

Originally Posted by eltoshan

No spring changes are allowed in stock class, so we need to make the most out of it with super large front sway bars and stiff shocks to keep the camber during sweepers. Camber and tires are by far the 335i's biggest weakness in stock class.

I actually might just do an STU build, and leave the r-comps and hardcore autocrossing to the SM 2G DSM that I'll hopefully be pickup.

STU ftw...the PAX is barely any different from stock class, and you can pretty much do anything except R-comps...but i hate how they don't allow stuff like cf hood and trunk

[eltoshan]

Originally Posted by Gen_E92

STU ftw...the PAX is barely any different from stock class, and you can pretty much do anything except R-comps...but i hate how they don't allow stuff like cf hood and trunk

Yeah, I think STU car would be more enjoyable to drive on the street as well.

Back on topic, what rear bar would be good? UUC is adjustable, is it worth it?

[BTM]

My setup and review may seem a little strange but I'll share it anyway. I am running non E93 M3 front with UUC rear, was previously running UUC front and rear.

I bought the car from a dealer, stupidly with my own "inspection" (looking for paintwork, bodywork, evidence of engine mods) and bought my car. Shortly after purchasing it started to be very noisy at the front, creaking and squeaking very audibly and embarrassingly at 30mph and below. Above these speeds I'm sure it was making just as much noise but it just wasn't audible. And this was not just a "grease the bushings" type noise, this was metal on metal contact - not good. Another strange nuance of the noise was that when the car was cold, so was the noise. As temp increased, the car got noisier. The car would get noisier and noisier the longer the trip. Took to the dealer, they said I had bought a car with aftermarket sways and they're not gonna do anything, take it back to who I bought it from. After getting the runaround from them for a week, I was basically told the would put it back to stock for $2400 or I could get lost. Anyone shopping for a BMW in Chicagoland would best avoid Bill Jacobs in Naperville - I'm far from the only one with a bad experience with them.

Luckily, I have a lift in my garage. Did some research, but not enough as I would've probably ended up with the E93 M3 bar as it's stiffer but bought the standard bar and put it in. I didn't want to screw around with dropping the rear end if I was happy with the results, so I was only doing front at this time.

Result - quiet! Mainly what I wanted. The handling is right on par with where it was, and the front actually felt a little tighter (probably due to replacing the bushings with new ones). In comparison to cars with just ZSP, this is definitely favorable to me, as the rear rotates a little better, but doesn't threaten to snap on you and has never made me feel uncomfortable.

I can't comment on how many miles are on the UUC, and I seem to have an isolated experience with the interference. To be specific, the tie rods would knock against the bar... as evidenced by wear on the bar and rods, but just surface wear I did not feel I needed to replace the rods. I tried it on all adjustment settings and could not get it to work, and it appeared it was installed properly (not sure how one could install this one upside down since it comes pre-packed)

[ThreeseriesFTW]

Thanks for the compilation! This shoulda been stickied

[NiVeDh]

This is an old thread but lots of good information here - it helped me!

[scflaw]

Great info guys but i was wondering if it was true or not. I had called BMW parts HKG for a quote on M3 sways and he warned me that m3 anti roll bars on a 335i e93 would have a chance of tearing apart my undercarriage (i'm assuming the plastic covering, etc)?

*edit* i'm not trying to be a troll, this actually happened and i just wanted to know if it was a good option to upgrade the front sways on my e93 to m3 e93 sways.