Suspension overhaul on my 2008 135i

[EM58NDS 135i]

Right then guys, i have been busy buying lots of chassis and suspension parts over the last few months, and i am pretty much ready to begin the complete overhaul of my 135i's handling.

Here is a run down of what i have purchased so far:-

ST Suspension STXA Coilover Kit (Height & dampner control)



E92 M3 Front Upper Control Arms
E92 M3 Front Lower Control Arms
E92 M3 Front Upper Inner Bushings
E92 M3 Front Sway Bar, Bushes & Mounts

E92 M3 Rear Guide Rods
E92 M3 Upper Link Arms (Wishbone)
E92 M3 Brake Sensor Brackets
E92 M3 Rear Subframe Bushings (Front)
E92 M3 Rear Subframe Bushings (Rear)
E92 M3 Rear Sway Bar, Bushes & Mounts
Megan Racing Adjustable Rear Toe Control Arms
Megan Racing Adjustable Rear Trailing Arms

There is afew questions i need to ask before i continue with the install though.

1) The car won't be going mega low, so i am assuming i will not need to purchase any aftermarket adjustable rear camber arms, such as the Megan Racing ones? The rear OE camber arms should have more than enough adjustability right?

2) Do you think it is wise to also replace the sway bar end links when fitting the new sway bars front and rear, or do you think the stock ones will be fine? (on 37k miles atm). If so, standard ones should be fine again i assume? No need for any uprated or adjustable ones with M3 bars.

3) Is there any particular order in which i should go about having all these parts installed? Should i do the coilovers first? Or do al the arms and sway bars first? Or maybe try to get everything fitted in one single hit? Also, if you think i am missing anything, or something else i can do to improve the handling, let me know. Any extra advice on this would be great. Thanks

[swagon]

I'm not an expert, but just for the sake of finding out what component does what and how it betters the suspension I'd do the coilovers and bushings first and then follow with other stuff, however, you had bought a lot of things so that would be pricey if you're not going to do it by yourself.

Curious to hear about the coilovers. Debating between those (or XTAs) and KW SCs. I guess their new X range is brand new as I have read almost anything about them.

[ilikebmxbikes]

Originally Posted by EM58NDS 135i

Right then guys, i have been busy buying lots of chassis and suspension parts over the last few months, and i am pretty much ready to begin the complete overhaul of my 135i's handling.

Here is a run down of what i have purchased so far:-

ST Suspension STXA Coilover Kit (Height & dampner control)



E92 M3 Front Upper Control Arms
E92 M3 Front Lower Control Arms
E92 M3 Front Upper Inner Bushings
E92 M3 Front Sway Bar, Bushes & Mounts

E92 M3 Rear Guide Rods
E92 M3 Upper Link Arms (Wishbone)
E92 M3 Brake Sensor Brackets
E92 M3 Rear Subframe Bushings (Front)
E92 M3 Rear Subframe Bushings (Rear)
E92 M3 Rear Sway Bar, Bushes & Mounts
Megan Racing Adjustable Rear Toe Control Arms
Megan Racing Adjustable Rear Trailing Arms

There is afew questions i need to ask before i continue with the install though.

1) The car won't be going mega low, so i am assuming i will not need to purchase any aftermarket adjustable rear camber arms, such as the Megan Racing ones? The rear OE camber arms should have more than enough adjustability right?

2) Do you think it is wise to also replace the sway bar end links when fitting the new sway bars front and rear, or do you think the stock ones will be fine? (on 37k miles atm). If so, standard ones should be fine again i assume? No need for any uprated or adjustable ones with M3 bars.

3) Is there any particular order in which i should go about having all these parts installed? Should i do the coilovers first? Or do al the arms and sway bars first? Or maybe try to get everything fitted in one single hit? Also, if you think i am missing anything, or something else i can do to improve the handling, let me know. Any extra advice on this would be great. Thanks

First off - Excellent choice going full M3 stuff. You will instantly notice an enormous improvement on the car.

One thing to note, the 135i and m3 rear subframes are different and the rear toe arms are different length. If you get adjustable rear toe arms make sure they are 135I/335i and not M3.

1) your fixed arms will be fine.

2) you can replace the sway bar end links in the front with adjustable ones, but as you noted, you are not going too low so you would likely be more than fine with your stock ones.

3) You will save the most if you do it all at once. You will share a lot of labor on the installs. Rear bar and rear subframe bushings combine labor, and just the act of lifting the car up and doing coilovers etc. saves some time on the control arms. The only thing you are missing from your list is a Limited Slip diff.

[EM58NDS 135i]

Swagon:- Yes, this is the brand new range of coilovers that ST have just started producing. The box had KW logo's all over it, as they are built in the same factory. Personally, i would not waste the extra money on actual KW's and get the ST version instead. The ST-XA is equivalent to KW-V2 IIRC.

ilikebmxbikes:-Thanks for your input. Yes, i did indeed purchase the 135i Megan Racing rear toe arms. It's taken me the best part of 3 months to buy all these parts, as they certainly came at a price! The conservatory looks like a BMW parts center lol. I will speak with my mechanic, and see if he is happy to install everything in one hit. Then i can go get an alignment done the next day, or same day if time allows.

With regards to an LSD, that is certainly on the to do list, along with poly diff mounts, but they won't be until further down the line. Those Quaife diff's are pricey ey!

[Southjersey128]

Originally Posted by EM58NDS 135i

Swagon:- Yes, this is the brand new range of coilovers that ST have just started producing. The box had KW logo's all over it, as they are built in the same factory. Personally, i would not waste the extra money on actual KW's and get the ST version instead. The ST-XA is equivalent to KW-V2 IIRC.

ilikebmxbikes:-Thanks for your input. Yes, i did indeed purchase the 135i Megan Racing rear toe arms. It's taken me the best part of 3 months to buy all these parts, as they certainly came at a price! The conservatory looks like a BMW parts center lol. I will speak with my mechanic, and see if he is happy to install everything in one hit. Then i can go get an alignment done the next day, or same day if time allows.

With regards to an LSD, that is certainly on the to do list, along with poly diff mounts, but they won't be until further down the line. Those Quaife diff's are pricey ey!

I would hold off on the M3 rear sway until you get the LSD. The inner wheel will break free very easily when pulling a way with the front wheels turned. (Like when pulling out into traffic from a side street). Mine does and I only have a 128i. Its the one thing about my suspension Im not happy with. Im swapping it out with a 335xi one that I have. The LSD's that are out there are not compatible with the automatic 128i's, so I can't put one in.

[A_Squared]

Pretty sure those ST XA are Europe only right? Never saw them as an option when I just bought my ST's a few weeks ago

[chris82]

Originally Posted by EM58NDS 135i

Swagon:- Yes, this is the brand new range of coilovers that ST have just started producing. The box had KW logo's all over it, as they are built in the same factory. Personally, i would not waste the extra money on actual KW's and get the ST version instead. The ST-XA is equivalent to KW-V2 IIRC.

ilikebmxbikes:-Thanks for your input. Yes, i did indeed purchase the 135i Megan Racing rear toe arms. It's taken me the best part of 3 months to buy all these parts, as they certainly came at a price! The conservatory looks like a BMW parts center lol. I will speak with my mechanic, and see if he is happy to install everything in one hit. Then i can go get an alignment done the next day, or same day if time allows.

With regards to an LSD, that is certainly on the to do list, along with poly diff mounts, but they won't be until further down the line. Those Quaife diff's are pricey ey!

I don't believe the ST has the corrosion resistance coating or material that the KWs have. I think that is why the KW cost more. If you live in an area where you don't see rain, or you don't drive it through the winter I mean sure go with the ST. But most people will want that corrosion resistance. You get what you pay for

[EM58NDS 135i]

Taken from the ST website.

http://www.st-suspensions.net/st/inf...t_xa_coilovers

KW Engineering: Exclusive for ST suspension

The high-quality ST XA coilover is based on the twin-tube damping principle of low friction combined with pressure-resistant damper housings. Manufactured directly at KW, a mono block guide and seal package reduces the friction of the damper as well as protecting it against corrosion and dirt. Each galvanized strut is sealed multiple times to ensure maximum longevity in ALL weather conditions.

Galvanized coilover struts with additional coating for an optimized corrosion protection
Complete solution with adjustable spring plate, race spring system and bumpers with dust protection

I'm sure they will be fine :-)

[chris82]

Originally Posted by EM58NDS 135i

Taken from the ST website.

http://www.st-suspensions.net/st/inf...t_xa_coilovers





Galvanized coilover struts with additional coating for an optimized corrosion protection
Complete solution with adjustable spring plate, race spring system and bumpers with dust protection

I'm sure they will be fine :-)

Yes but it is galvanized steel not stainless steel. That is why they are less expensive. I am just pointing it out as I noticed you live in the UK which is never short on rain

[swagon]

So any updates?

[EM58NDS 135i]

Yeah, they were fitted this weekend. Difference is night & day between how the car drove and felt before and how it drives now with all the M3 components and ST coilovers.

[swagon]

Oh man

So can you really confirm that the XAs are worth buying? I found a slightly used set of them for an interesting price... How low did you set them, because the drop is spot on (not that I want to slam the car, but 20-25 mm would be nice). Interested in better comfort and handling, the stock kit is too harsh while being soft.

Thank you very much.

[Fidiman]

I would like to know how it handled vs KW v1/v2/v3 because these coilovers are very affordable !

[EM58NDS 135i]

Originally Posted by swagon

Oh man

So can you really confirm that the XAs are worth buying? I found a slightly used set of them for an interesting price... How low did you set them, because the drop is spot on (not that I want to slam the car, but 20-25 mm would be nice). Interested in better comfort and handling, the stock kit is too harsh while being soft.

Thank you very much.

Well 'in my opinion' yes, they are worth buying, they are great value for money. The back was on it's lowest setting, but i have since raised it 10mm to alleviate tyre scrubbing. I can't pass judgement on buying a second hand kit though, that's your call...

They certainly get rid of that harshness that the BMW M Sport kit has. It's a firmer yet smoother ride. I can't fault it for road use.

[swagon]

Originally Posted by EM58NDS 135i

Well 'in my opinion' yes, they are worth buying, they are great value for money. The back was on it's lowest setting, but i have since raised it 10mm to alleviate tyre scrubbing. I can't pass judgement on buying a second hand kit though, that's your call...

They certainly get rid of that harshness that the BMW M Sport kit has. It's a firmer yet smoother ride. I can't fault it for road use.

That's exactly what I'm looking for. Smoother, yet firmer ride for the spirited driving. The roads here are very bad, too. The problems is that with that guy selling the coilovers you're the only who has got these STs on an E82, so not really a lot of feedback.