[2e9x's]

I own both...an e90 335i with sport and e92 335i with sport.

Over the past week I have been driving the e90 and it seems to me like the e90 just drives...better. Wondering why, I have spent some time on realoem.com

What I found, in comparing the suspension part numbers, is that the e90 sport shocks can be either Sachs OR Bilstein. The same options are not listed on the e92 page.

e92:
No. Description Supplement Qty From Up To Part Number Price Notes
01 LEFT FRONT SPRING STRUT SACHS 1 09/2006 31306771179 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 09/2006 31316786003
01 FRONT RIGHT SPRING STRUT SACHS 1 09/2006 31306771180 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 09/2006 31316786004
01 LEFT FRONT SPRING STRUT 1 09/2006 05/2008 31316780079
01 LEFT FRONT SPRING STRUT 1 09/2006 31316785591
01 FRONT RIGHT SPRING STRUT 1 09/2006 05/2008 31316780080
01 FRONT RIGHT SPRING STRUT 1 09/2006 31316785592

e90:

Interesting reading...so up until 3/2007 there was a standard suspension and a Sport suspension. Then after 3/2007 there was standard and M Sport. I am pasting the entire page from realoem.com

01 LEFT FRONT SPRING STRUT SACHS 1 31306771177 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 31316786001
01 FRONT RIGHT SPRING STRUT SACHS 1 31306771178 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 31316786002
01 LEFT FRONT SPRING STRUT BILSTEIN 1 31316784973
01 FRONT RIGHT SPRING STRUT BILSTEIN 1 31316784974
01 LEFT FRONT SPRING STRUT SACHS 1 06/2008 31306771177 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 06/2008 31316786001
01 FRONT RIGHT SPRING STRUT SACHS 1 06/2008 31306771178 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 06/2008 31316786002
01 LEFT FRONT SPRING STRUT BILSTEIN 1 06/2008 31316784973
01 FRONT RIGHT SPRING STRUT BILSTEIN 1 06/2008 31316784974
FOR VEHICLES WITH
M SPORTS SUSPENSION
S704A=YES
01 LEFT FRONT SPRING STRUT SACHS 1 03/2007 31306771179 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 03/2007 31316786003
01 FRONT RIGHT SPRING STRUT SACHS 1 03/2007 31306771180 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 03/2007 31316786004
01 LEFT FRONT SPRING STRUT BILSTEIN 1 03/2007 31316784975
01 FRONT RIGHT SPRING STRUT BILSTEIN 1 03/2007 31316784976
01 LEFT FRONT SPRING STRUT SACHS 1 03/2007 06/2008 31306771179 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 03/2007 06/2008 31316786003
01 FRONT RIGHT SPRING STRUT SACHS 1 03/2007 06/2008 31306771180 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 03/2007 06/2008 31316786004
01 LEFT FRONT SPRING STRUT BILSTEIN 1 06/2008 31316784975
01 FRONT RIGHT SPRING STRUT BILSTEIN 1 06/2008 31316784976
FOR VEHICLES WITH
SPORTS SUSPENSION SETTINGS
S226A=YES
01 LEFT FRONT SPRING STRUT SACHS 1 01/2005 03/2007 31306771179 $180.79
01 LEFT FRONT SPRING STRUT SACHS 1 01/2005 03/2007 31316786003
01 FRONT RIGHT SPRING STRUT SACHS 1 01/2005 03/2007 31306771180 $180.79
01 FRONT RIGHT SPRING STRUT SACHS 1 01/2005 03/2007 31316786004


SO...my question is how do I know if my 10/2007 production e90 have the Sachs or Bilstein struts? Do you think that difference could account for the difference in how the cars drive?

TIA...sorry if this obvious to all of you and I appreciate your help.

[RedGT3]

Check this out.

[LaYzEe]

interesting. so does that mean the Bilsteins are better then the Sachs since the e92s only come with it?

[SixDegrees]

Might be that the the e90 being a 4 door has more body rigidy than the Coupe. Just a thought. The 4 door has stiff structural B pillars which might not be the same as the Coupe, so you may find that the suspension and body structure work better together.

Think of the differences you get with Coupes and Conv's.....

Might not just be a suspension only thing! I guess a real test would be 2 almost identical E90s, one with SACHS and the other Bilstein. Then you know that its really only the suspension thats different.

As a Coupe and Saloon (Sedan) have different body structure, rigidty, , flec, etc I think isolating it to suspension might be over simplifying it.

[2e9x's]

Originally Posted by LaYzEe

interesting. so does that mean the Bilsteins are better then the Sachs since the e92s only come with it?

I think only the e90 comes with the Bilsteins.

Still...it may be the body structure/stiffness. It may be the shocks. But I definitely think the e90 drives better.

[Mr. 5]

Just jack up the car and look at the part numbers of the shocks.
Tehn go to realoem and see if you have the bilsteins or the sachs.
My car came with the Sachs sport suspension 1179 fronts and 1729 rear.
Now I have the BMW Performance suspension.

I'm wondering if it has to do with the legths or weights of each car.
I think a lot of people don't know but the sedan is a little shorter than the coupe.
Is the weight different?

[Orb]

Originally Posted by SixDegrees

Might be that the the e90 being a 4 door has more body rigidy than the Coupe. Just a thought. The 4 door has stiff structural B pillars which might not be the same as the Coupe, so you may find that the suspension and body structure work better together.

Think of the differences you get with Coupes and Conv's.....

Might not just be a suspension only thing! I guess a real test would be 2 almost identical E90s, one with SACHS and the other Bilstein. Then you know that its really only the suspension thats different.

As a Coupe and Saloon (Sedan) have different body structure, rigidty, , flec, etc I think isolating it to suspension might be over simplifying it.

The e90 is not near as stiff as e92 coupe. You have a rear doors so it is not going to be stiffer no matter what you do...B piller or not.

Orb

[2e9x's]

So looking at BMWUSA.COM I find that the Sedan is 2.9" shorter than the Coupe on the same wheelbase. The Sedan is 34 pounds heavier (assuming my combination of a stick Coupe and automatic Sedan). The Sedan is 1.2" wider overall with the identical track. The Sedan is 3" taller than the Coupe. On this issue though I suspect the diagrams on BMWUSA.COM use non-sport e90 whereas the e92s all have sport package stock. So the real height difference between 2 sport package cars might be less. The Sedan has 1.1" less front overhang and 1.7" less rear overhang.

So with all those mind numbing statistics on the proverbial table we are left with...left with...the cars are so close that I seriously doubt that a tape measure will help too much to identify the cause.

Today I will jack the car up and take a look at the part numbers on the shocks. Maybe that will give more info.

Orb - Is it possible that the b-pillar on the Sedan might actually strengthen the side of the car, as opposed to the one large opening on the Coupe?

[Mr. 5]

I'm interested in what comes out of this.
I really like the handling of my e90, but I do notice the obvious and dreaded understeer.
I haven't driven the e92 so I can't compare, but I did drive an e90 M3 on Friday, and I'll tell you one thing...
I'm extremely happy that I have my 335.

Yes, I'm sure that if I were on a track all my life then the M3 would be the best, but for the daily driver, the 335 is way better with the torque that we have.
I have a feeling that if I had the M3, I would be shifting constantly just to keep it in the power band.

[Mr. 5]

Just for the record, these are my part numbers off of my BMW Performance Suspension:

Left Front Strut 31318036553
Right Front Strut 31318036554

Left Rear Shock 33528036026
Right Rear Shock 33528036026

I have no idea who these dampers are made by.

[2e9x's]

So today I was swapping the wheels between the cars (the e90's wheels have RFT's and the e92's have Dunlop Direzza Z1 Star Spec). By way of explanation my wife and I are swapping cars because I need the sedan to drive carpool. While doing the wheel swap I checked the part number for the front driver's side strut on the e90. What I can tell you is that it is the Sachs part number. Therefore both my cars have Sachs struts. The part number on the e90 Sachs strut is the same part number listed by realoem.com for the e92.

Eliminating shock absorber differences, sway bar differences or bushing differences, the only conclusion left is that the e90 body shell is the main issue. Unless of course the springs are different? realoem.com doesn't list the part numbers for the springs so I can't check.

As for acceleration the gearing would account for why the e90 feels quicker. That much I get. But the difference is pretty startling...

Slightly OT but I really like how the 162's look on the e92!!!!!!

[Fraggy]

Have you checked that both cars have the same tires with the same tire pressure? Sidewall stiffness and PSI can really affect not only the cars handling but also its ride as well. Two PSI too much and its like riding on rocks, 2 PSI too little and it gets nice and sloppy.

[2e9x's]

Originally Posted by Fraggy

Have you checked that both cars have the same tires with the same tire pressure? Sidewall stiffness and PSI can really affect not only the cars handling but also its ride as well. Two PSI too much and its like riding on rocks, 2 PSI too little and it gets nice and sloppy.

As I mentioned in my post above, they do NOT have the same tires. One car has OEM RFTs and the other has Dunlop Direzza Z1 Star Spec. I did, however, notice a difference when both cars still had RFTs.