F30POST
F30POST
2012-2015 BMW 3-Series and 4-Series Forum
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
BMW 3-Series and 4-Series Forum (F30 / F32) | F30POST > 2012-2019 BMW 3 and 4-Series Forums > General F30 Sedan / F32 Coupe / F36 Gran Coupe Forum > Close Look at F30 328i Suspension by Insideline!
GetBMWParts
Post Reply
 
Thread Tools Search this Thread
      02-14-2012, 10:22 AM   #1
E90 Skye
Lieutenant
E90 Skye's Avatar
United_States
34
Rep
499
Posts

Drives: E36 M3
Join Date: May 2009
Location: DFW, Texas

iTrader: (1)

Thumbs up Close Look at F30 328i Suspension by Insideline!

BIMMERPOST
     Featured on BIMMERPOST.com
pretty informative and great pics of the underside and part that counts of the new kid on the block!

http://blogs.insideline.com/straight...-bmw-328i.html

Quote:
The 2012 BMW 328i is the first example of the all-new 6th-generation 3 Series sedan (code name: F30) we've had in the shop.

It's hard to tell with the naked eye, but the footprint of BMW's volume seller has grown significantly. Longer overall by 4.3 inches, it now rides on a wheelbase that's 1.9 inches longer. And even though its overall width has shrunk by a scant 0.2 inches, the U.S.-spec 2012 328's tires have been spread farther apart by 1.2 inches up front and 2.3 inches out back. Despite all this, the curb weight of a 328i manual only increases by 44 pounds.

In CAFE terms, the footprint has been increased 5 percent, from 44.8 square feet to 46.9 square feet. That's interesting because cars with bigger footprints have less aggressive fuel economy increase targets. And the new CAFE standards only regulate the footprints you build in a given year, not the footprints you built last time out. At least in part, this size growth may be an example of strategic upsizing for CAFE purposes.

But such regulatory talk is boring. Let's see the metal.

Along the way you might want to open my walkaround of a 2009 BMW 3 Series in another window. That one was an M3, so you'll see more aluminum, but you can still see how the basic architecture differs...or doesn't.

Name:  f30suspension1.jpg
Views: 54863
Size:  60.5 KB

Even though the detail dimensions are different, the basic 3 Series suspension philosophy remains. This is still a strut-based front suspension.



Name:  f30suspension2.jpg
Views: 88718
Size:  72.4 KB

As before, this is a "dual link" strut, in that it uses two distinct links (green), each with their own ball joint, instead of a single lower control arm and one lower ball joint.

The front stabilizer bar is direct-acting via an elongated stabilizer link (yellow) that connects directly to the strut housing.



Name:  f30suspension3.jpg
Views: 57562
Size:  58.5 KB

The key advantage of this arrangement is the ability to move the virtual steering pivot point outboard to a spot that would be physically impossible with a single ball joint. This in turn allows the engineers to reduce the scrub radius and do other cool things with steering geometry. Of course the "instantaneous virtual" intersection point shown above is constantly moving, so figuring it out properly is a bit more complicated than just overlaying a couple of yellow lines.



Name:  f30suspension4.jpg
Views: 46185
Size:  41.1 KB

Pretty neat, huh?



Name:  f30suspension5.jpg
Views: 73930
Size:  76.8 KB

Among all that aluminum there's a front suspension height sensor (green) and we can just see the bottom of the twin-tube front strut (yellow).



Name:  f30suspension6.jpg
Views: 54299
Size:  81.4 KB

One of the "tells" that gives away the twin-tube strut is this (green) flattened section for tire clearance. And this mechanism (yellow) shows that this 3 Series is equipped with the "Adaptive M Sport" suspension with electronically controlled dampers. The height sensor we saw previously is one of several inputs that feed into the controlling ECU.



Name:  f30suspension7.jpg
Views: 50800
Size:  67.4 KB

The 328i's brakes, meanwhile, are comprised of single-piston floaters (green) and ventilated rotors. One of the openings in the front grille (yellow) brings in cool air.



Name:  f30suspension8.jpg
Views: 47303
Size:  84.0 KB

Peel back the diagonal hood seals on either side and you'll find a strut tower brace (yellow) that ties into the firewall.



Name:  f30suspension9.jpg
Views: 46983
Size:  63.6 KB

Hard to tell what's going on in back from this angle. Nicely finished wheel well, though.



Name:  f30suspension10.jpg
Views: 58438
Size:  94.5 KB

The rear of the new 3 Series is propped up by a 5-link multilink setup that's similar, but not identical, to last year's. It's almost impossible to see all five links in one shot, but we'll eventually catch up with all of them.

As we've seen many times before, the two upper links (green) approximate an upper A-arm. The forward-most of the two lower links (yellow) is visible, but the rearmost one is not because it's behind the shock. The slender link at the rear (orange) is the toe link.



Name:  f30suspension11.jpg
Views: 76787
Size:  99.8 KB

From this vantage point we can see the missing link (yellow), a massive affair that also carries the spring and shock absorber. The toe link (green) we saw in the last shot sits just above it. Both of them have eccentric cams built into their inner attachment points; the lower one is for camber and the upper one is for toe.



Name:  f30suspension12.jpg
Views: 52365
Size:  94.8 KB

This head-on view of the same links shows the eccentric cams a bit more clearly. It also shows us the motion ratio of the spring to be about 0.60-to-1 and that of the shock to be about 0.85-to-1, not unlike the outgoing generation.



Name:  f30suspension13.jpg
Views: 53877
Size:  80.6 KB

The underneath view (my new favorite) shows just how the two lower links work together. None of this was all that visible until I first removed an aerodynamic cover that fastens to four tiny bolts that surround the spring pocket.



Name:  f30suspension14.jpg
Views: 49598
Size:  90.1 KB

A smallish (but big enough) rear stabilizer bar (green) snakes between the upper links on the way to meet its own drop link.



Name:  f30suspension15.jpg
Views: 47488
Size:  68.4 KB

That link is made of high-grade plastic and has ball joints on both ends. It attaches directly to the knuckle at a 1-to-1 motion ratio.
Right next door stands another twin-tube shock with electronically adjustable damping.



Name:  f30suspension16.jpg
Views: 48092
Size:  82.6 KB

Wherever there are computer-controlled shocks there will also be suspension position sensors.


Continued at http://blogs.insideline.com/straight...-bmw-328i.html
__________________
CURRENT - E36 M3 Alpine White | BC Coils | FROMERLY - 2006 Jet Black 330i | Premium Package | ZF AT | LUX 4.0 | Jlevi M3 Front Bumper | CF Mtech spoiler | Gloss Black Grill | Msport wheel | Blacklines | Koni FSD + Eibach Pro-kit | BMS PBX
Appreciate 0
      02-14-2012, 11:38 AM   #2
Nero7
Second Lieutenant
Nero7's Avatar
53
Rep
258
Posts

Drives: F30 M-Sport 328i
Join Date: Apr 2011
Location: Sweden

iTrader: (0)

Awesome, thanks for sharing
__________________

/// M-Sport 328i // Packages -- Adaptive Drive-- Drive Comfort -- Function -- Visibility // 19" 403M // M-Sport Brakes // Harman Kardon // Head Up Display ///
Appreciate 0
      02-14-2012, 12:46 PM   #3
JoeyO
Captain
United_States
202
Rep
814
Posts

Drives: silver car
Join Date: Jan 2012
Location: USA

iTrader: (0)

It's amazing something that complex still works after all the sand and salt gets in there after years of driving (particularly here in the northern snow-belt).

I love gizmos and sensors, but I don't like that they increase the likelyhood of something failing.
Appreciate 0
      02-14-2012, 01:27 PM   #4
jon328i
Wheelmaster
jon328i's Avatar
United_States
14
Rep
445
Posts

Drives: F39, S209, VB-WRX
Join Date: Sep 2010
Location: Los Angeles

iTrader: (7)

nice information!
Appreciate 0
      02-14-2012, 02:51 PM   #5
noro
Colonel
noro's Avatar
Armenia
90
Rep
2,707
Posts

Drives: '91 M3, '04 E46 ZHP, '72 2002
Join Date: Aug 2006
Location: Boston

iTrader: (0)

Nice pictorial,

One thing was not mentioned here is that with the M-Sport suspension there is an additional sensor on the strut housing that is an accelerometer, it detects the rate of changes with which the suspension travels up and down (not to be confused with the height sensor).

All and all, I think a regular sport suspension equipped car with a nice set of lightweight wheels and tires (totaling ~40lb) will be a far better improvement to the car than an m-sport suspension setup.

13 x 4 x ~5 = 260lbs dead weight equivalent.
__________________
zhpregistry.net - ZHP stats and free classifieds.
Appreciate 0
      02-14-2012, 02:59 PM   #6
cjh
Enlisted Member
51
Rep
47
Posts

Drives: 22 G42
Join Date: Jan 2012
Location: Michigan

iTrader: (0)

Quote:
Originally Posted by JoeyO View Post
It's amazing something that complex still works after all the sand and salt gets in there after years of driving (particularly here in the northern snow-belt).

I love gizmos and sensors, but I don't like that they increase the likelyhood of something failing.
I was thinking the same thing. Incredible how durable the components must be in order to work for the 20+ years that the car is on the road.
Appreciate 0
      02-14-2012, 03:17 PM   #7
pcbrew
Captain
pcbrew's Avatar
29
Rep
784
Posts

Drives: 2012 335i 6MT
Join Date: Jun 2010
Location: DFW

iTrader: (0)

Quote:
Originally Posted by noro View Post
One thing was not mentioned here is that with the M-Sport suspension there is an additional sensor on the strut housing that is an accelerometer, it detects the rate of changes with which the suspension travels up and down (not to be confused with the height sensor).

All and all, I think a regular sport suspension equipped car with a nice set of lightweight wheels and tires (totaling ~40lb) will be a far better improvement to the car than an m-sport suspension setup.

13 x 4 x ~5 = 260lbs dead weight equivalent.
I don't understand your equation.
Standard wheels & tires are 53 lbs each or 212 lbs unsprung weight.
What would lightweight wheels & non-RFT tires weigh?

How do you estimate unsprung weight of active suspension pieces?
Appreciate 0
      02-14-2012, 03:36 PM   #8
noro
Colonel
noro's Avatar
Armenia
90
Rep
2,707
Posts

Drives: '91 M3, '04 E46 ZHP, '72 2002
Join Date: Aug 2006
Location: Boston

iTrader: (0)

Quote:
Originally Posted by pcbrew View Post
I don't understand your equation.
Standard wheels & tires are 53 lbs each or 212 lbs unsprung weight.
What would lightweight wheels & non-RFT tires weigh?

How do you estimate unsprung weight of active suspension pieces?
Basically I am saying that if given the choice of lightweight wheels/tires vs m-sport I would pick light weight. The effect of rotational mass on the car is far more pronounced than stationary weight at a rate of ~ 1 to 5 (varying based on what is happending with the car at the moment). Meaning that if you drop each corner by 13 lbs you will get the same effect as having ~200lbs lighter car.
__________________
zhpregistry.net - ZHP stats and free classifieds.
Appreciate 0
      02-14-2012, 05:07 PM   #9
DrivenByE30
Brigadier General
DrivenByE30's Avatar
France
578
Rep
3,870
Posts

Drives: '12 F30 Lux 335i 6MT
Join Date: Jun 2011
Location: OC - SoCal

iTrader: (0)

One of the best, if not the best thread regarding the F30 in a few weeks now! Props for the explaination and the pointers!!! I love it... being an engineer myself
Appreciate 0
      02-14-2012, 05:39 PM   #10
jbres79
Private
4
Rep
52
Posts

Drives: SS/GTI/335xi M Sport
Join Date: Jan 2012
Location: Windsor, ON, Canada

iTrader: (0)

do all F30's have single piston front brakes?
Appreciate 0
      02-14-2012, 07:44 PM   #11
Ron Scott
Captain
85
Rep
632
Posts

Drives: 2013 335 M Sport
Join Date: Feb 2010
Location: Long Island

iTrader: (0)

Quote:
Originally Posted by E90 Skye View Post
The key advantage of this arrangement is the ability to move the virtual steering pivot point outboard to a spot that would be physically impossible with a single ball joint. This in turn allows the engineers to reduce the scrub radius and do other cool things with steering geometry.[/I]
Does anyone know what the actual scrub radius is on the F30 328i vs. 335i? Also, what "cool things" have the engineers done with the steering geometry in both cars?

Gotta make a buy decision soon...

Thx.
Appreciate 0
      02-14-2012, 09:42 PM   #12
rideontwo
Lieutenant
190
Rep
428
Posts

Drives: VaNOs
Join Date: Jul 2008
Location: NE

iTrader: (1)

Stamped steel rear suspension components? I could have swore that everything on the E90/E92 (non-m3) was aluminum.
Appreciate 0
      02-15-2012, 04:06 AM   #13
cstavaru
Brigadier General
cstavaru's Avatar
306
Rep
3,262
Posts

Drives: 2009 335i M Sport Sedan 6MT
Join Date: Aug 2008
Location: Bucharest, Romania

iTrader: (0)

Nice article ! The suspension is very similar to the e90 suspension. The e90 even has some links in the rear made from aluminium. But I suppose BMW chose steel on the F30 to help offset the extra front weight due to the bigger front overhang and maintain the 50/50 weight balance front/rear.

You can lower the unsprung weight by 10lbs per corner by getting some well-chosen non-runflat tires (like Continental DW for summer or Continental DWS for all-season - they are both very light) and exchanging the wheels with 20lbs semi-forged wheels which can be had for about $900 a set and are quite strong. This way a wheel/tire combo will weight like 43lbs, as opposed to 53lbs. With this kind of setup I would bet you will gain like 0.4s in the 0-62mph sprint.
Appreciate 0
      02-15-2012, 08:14 AM   #14
noro
Colonel
noro's Avatar
Armenia
90
Rep
2,707
Posts

Drives: '91 M3, '04 E46 ZHP, '72 2002
Join Date: Aug 2006
Location: Boston

iTrader: (0)

Quote:
Originally Posted by rideontwo View Post
Stamped steel rear suspension components? I could have swore that everything on the E90/E92 (non-m3) was aluminum.
yup, aluminum cast is far more expensive. I personally look at it as step backwards. That said it all depends if the new steel components are actually lighter and/or stronger because of its hollow design.
__________________
zhpregistry.net - ZHP stats and free classifieds.
Appreciate 0
      02-15-2012, 08:16 AM   #15
noro
Colonel
noro's Avatar
Armenia
90
Rep
2,707
Posts

Drives: '91 M3, '04 E46 ZHP, '72 2002
Join Date: Aug 2006
Location: Boston

iTrader: (0)

Quote:
Originally Posted by Ron Scott View Post
Does anyone know what the actual scrub radius is on the F30 328i vs. 335i? Also, what "cool things" have the engineers done with the steering geometry in both cars?

Gotta make a buy decision soon...

Thx.
I have a feeling you mean turning radius, scrub radius is something different and is the same for both.
__________________
zhpregistry.net - ZHP stats and free classifieds.
Appreciate 0
      02-15-2012, 08:26 AM   #16
E90Fleet
Lieutenant General
South Africa
1307
Rep
10,185
Posts

Drives: BMW
Join Date: Apr 2005
Location: South Africa

iTrader: (0)

Quote:
Originally Posted by jbres79 View Post
do all F30's have single piston front brakes?
No, 335i has 4 piston front brakes
__________________
BMW if you are reading, I need a job, Please.
Appreciate 0
      02-15-2012, 09:13 AM   #17
E90 Skye
Lieutenant
E90 Skye's Avatar
United_States
34
Rep
499
Posts

Drives: E36 M3
Join Date: May 2009
Location: DFW, Texas

iTrader: (1)

Quote:
Originally Posted by E90Fleet View Post
No, 335i has 4 piston front brakes
is that optional?

also if you go to the actual link of the article the front suspension control arm links are animated, so you can see the actual movements associated with turning the wheel.
__________________
CURRENT - E36 M3 Alpine White | BC Coils | FROMERLY - 2006 Jet Black 330i | Premium Package | ZF AT | LUX 4.0 | Jlevi M3 Front Bumper | CF Mtech spoiler | Gloss Black Grill | Msport wheel | Blacklines | Koni FSD + Eibach Pro-kit | BMS PBX

Last edited by E90 Skye; 02-15-2012 at 09:29 AM..
Appreciate 0
      02-15-2012, 09:49 AM   #18
positiveions
Lieutenant General
positiveions's Avatar
Lebanon
961
Rep
11,722
Posts

Drives: 19 Tacoma, 16 Golf wagon
Join Date: Sep 2007
Location: Upland, CA

iTrader: (2)

Garage List
gone are the days when slapping a suspension was a simple task followed by a nice ice cold beer.
Oh well, can't beat them, join them.
Appreciate 0
      02-15-2012, 10:09 AM   #19
Black Flagged
Captain
Black Flagged's Avatar
United_States
470
Rep
778
Posts

Drives: M2C
Join Date: Dec 2011
Location: 91739

iTrader: (0)

Thumbs up

thanks for the cool info,that was interesting info....
Appreciate 0
      02-15-2012, 10:24 AM   #20
USC2000
Lieutenant Colonel
USC2000's Avatar
United_States
127
Rep
1,604
Posts

Drives: F30 328i M Sport
Join Date: Jul 2007
Location: El Paso, TX

iTrader: (10)

Really cool and interesting article.
__________________
2014 Alpine White 328i M Sport | M Performance Exhaust | M Performance Front Splitter | M Performance Carbon Fiber Spoiler | M Performance Grills | M Performance Pedals[/SIZE]
______________________
Appreciate 0
      02-15-2012, 10:37 AM   #21
z51vette
Registered
0
Rep
3
Posts

Drives: N54 535
Join Date: Feb 2012
Location: NY

iTrader: (0)

Front looks cool. Rear looks more of a cost cutting move than anything. Really hate seeing stamped steel driving behind a car. I was very surprised when I saw it for the first time.
Appreciate 0
      02-15-2012, 10:57 AM   #22
speedfan
Major
speedfan's Avatar
Vietnam
140
Rep
1,108
Posts

Drives: BMW
Join Date: Dec 2010
Location: HCM City

iTrader: (2)

*bookmarked*
GREAT INFO. Thanks for taking time to do this.
__________________
My e90

Frozen Grey. Dry CF Roof. Vorsteiner Double Sided CF Boot Lid. OSS. BMW Performance Aero Kit. BMW Performance CF Diffuser Cover. BMW Performance CF Trim. Robson Design Steering Wheel. Advan RS. Michelin PSS. H&R Touring Cup Kit. BMW Performance Brakes. Eisenmann Race Rear Muffler. ESS Directflash
Appreciate 0
Post Reply

Bookmarks

Tags
3 series f30, 3 series f30 forum, 3 series f30 suspension, 3 series forum, 328i f30 suspension, 328i suspension, bmw 3 series forum, bmw 3-series f30, bmw f30, bmw f30 3-series, f30 3 series suspension, f30 3-series, f30 3-series forum, f30 328i suspension, f30 forum, f30 forums, f30 suspension

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 01:22 AM.




f30post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST