[LotusBMW]

I've got a fairly clear path on power and reliability mods for my 335, but now to plan for handling. First up I'll be installing a Quaife ATB LSD. No rear drive car is complete without an LSD! The suspension is an area I'm unsure of. It's a daily, will never see the track so comfort is a priority. That said I will want my fun in the twisties or even on the greasy roads on the way to work each day. The car needs to have enough suspension control to hold power slides and ideally quell any axle tramp that may exist. I believe full coil overs are best from what I've read so interested in opinions on the options here. BC and PSSX seems to be the go. What else? M3 rear subframe bushes? Sway bars?

I'm most interested in people's' opinions based on actual experience.

Many thanks.

[JJH]

Given the benefit of hindsight, I definitely agree with your plan to install a LSD early on in the mod process; in my case a Quaife as well. Apart from a tune, nothing improves the performance in these cars as much as a LSD.

Like you, I only had a road car in mind when choosing my mods. I personally did not see the benefit of coil overs, I opted instead to ensure a quality set up that would be a big improvement on the standard suspension in the handling department, retain a decent comfort level and looked a bit more aggressive. For me, Koni Yellow ’adjustables’ and Eibach Pro Kit springs were perfectly suited for the job. Opinions will differ on this for sure.

Add to that, M3 control arms/wishbones front and rear, plus the M3 rear sub-frame bushes and a COMPETENT operator to align the new suspension and components is a MUST to complete the set up.

[LotusBMW]

Thanks for your input. Now I've come across a complication and that is my car is a wagon (E91). I note from Turner's website they only quote E90/92 and I've just run Just Jap regarding the BC range and they've told me the wagon rear will not match either the coupe or the sedan suspension...I'll drop TMS a line and see what they think.

[DR-JEKL]

What Jon has suggested is on the $.

I know this guy installed german Weitec coilovers on his E91

http://www.detailingworld.co.uk/foru...d.php?t=280698

[LotusBMW]

Love that look. Might use it as inspiration...

[LotusBMW]

I thought I'd scoured the TMS site carefully but it seems not. I wrote to them and they sent me this link. Seems the 335i is not available in the US as an E91, but all the non 4wd suspension for 325s and 328s also are appropriate for the E91 335. Same body and same engine weight out front. Just need to ensure the right level of comfort / sportiness is selected...I can relax again....

http://www.turnermotorsport.com/sear...SearchId=72751

[JJH]

Originally Posted by DR-JEKL

What Jon has suggested is on the $.

Thanks Shane

Armed with that info from Turner about E91 fitments, you need to also check out ECSTuning and locally for comparison. Again, not knowing your budget, I stress you should consider the cost/benefit of upgraded suspension vs. coilovers.

Cheers,
Jon

[LotusBMW]

Originally Posted by JJH_335

Thanks Shane

Armed with that info from Turner about E91 fitments, you need to also check out ECSTuning and locally for comparison. Again, not knowing your budget, I stress you should consider the cost/benefit of upgraded suspension vs. coilovers.

Cheers,
Jon

I'm certainly taking on board all feedback. Budget is a concern, as always, especially as I'm sure there is more than springs / shocks or coilovers to achieve what I want. The Koni kits on ECST are about $900 versus an HR coilover kit of $1,200 so not a massive difference. I've not yet looked into the relative quality and outcome of each option yet. I can't see that the ECST are E91 specific either but I'll figure all of that out in due course.

Who are the local options? BC do not do an E91 combo and said they will be totally different to E90/92/93.

Thanks for your input.

[JJH]

Originally Posted by LotusBMW

Who are the local options?

Stuart at BMR Autowerkes, a forum sponsor too.

[LotusBMW]

Originally Posted by JJH_335

Stuart at BMR Autowerkes, a forum sponsor too.

Thanks. Left him a message and dropped him an email yesterday. Be interesting to see what he comes up with. I've also emailed ECST and watched an installation video.

[donR]

I have been looking at suspension upgrades for my E91 as well. From past experience on my Audi estate with stock RS suspension I have found the upgrade to fatter H&R roll bars was an improvement for understeer & balance and Bilstein PSS9s/10s were a vast improvement for cornering such that my 2001 Audi estate handles better than my 2008 E91 m-sport.

I have been considering going the same route with the E91 but the PSS9/10s are a little pricey and perhaps overkill for the family shopping cart.

I thought the BCs would be compatible? and are a great price. I think the corner weights would only be marginally different and the biggest change would come from fuel and passenger load. My only concern was they are not progressive springs?

I can't see why any E90 suspension set would not work with an E91?

In the past I have used the Yellow Koni Sport adjustable shocks in an old E30 with H&R sport spings and K-mac anti-roll bars and they do perform very well but if I recall the rears are not as easy to adjust, but you want them softer anyway.

One thing to consider about the PSS9/10s is they are progressive springs so the ride is remarkably good until you start throwing it around. I think a lot of the cheaper coil overs are not progressive. Though correct me if I'm wrong.

People rave about KWs but I have not tried them and they are a similar price to the PSS9/10s in V2 & 3 so are also expensive.

I think the stock M-sport spring height is fairly good for daily driving so perhaps the adjustable koni damper kit & up rated anti-roll bars would be a good compromise and not too costly.

I like the idea of replacing a lot of the suspension parts with lighter M3 parts but sounds like a lot of work to me and expense, let a lone getting hold of them.

Similarly, the LSD would be great for when you are booting it out of corners and tracking or in the wet but I would think you would have to be pushing pritty hard on dry twisty's to really work it which in any case you might spin off and crash.

Anway, I'd also be interested to hear what people find works best.

Thanks Don

[JJH]

Originally Posted by liteonled

I like the idea of replacing a lot of the suspension parts with lighter M3 parts but sounds like a lot of work to me and expense, let a lone getting hold of them.

Similarly, the LSD would be great for when you are booting it out of corners and tracking or in the wet but I would think you would have to be pushing pritty hard on dry twisty's to really work it which in any case you might spin off and crash.

The M3 arms/wishbones are very easy to source (locally or OS) and are available as genuine or as OEM at a much reduced cost. Fitting can be DIY or done by your mechanic for little cost. Even less if you are upgrading your suspension at the same time. Alignment is especially critical when the front M3 arms go in BTW.

Anyone with a 335i running a tune, and especially if FBO, will be missing out on the huge performance improvement delivered by the tune if an LSD is not fitted.

[LotusBMW]

Sif not have an LSD...

[lemonpark]

I just want a LSD to do mad skids lol... and also so people can't say BMW is a single spinner (

Ps. I'm joking about the skids cos sarcasm doesn't work over the internet

[Scotty89]

Getting cheap coil overs will be a mistake.

For the price of "cheap" coil overs, you could instead get some decent spring/shock kits which are optimised for street use, and cause much less hassle.

Unless you're going to be tracking your car and pushing it to the absolute limit (which I'd say you're not with a wagon), or unless you're going to absolutely slam it low... then you're not going to gain any more from coil overs over a spring and shock kit.

You're not going to get "better performance" by fine tuning spring rates, damping rates and rebound rates if it's a daily driven street car.

Just get some decent springs/shocks from a reputable brand, and never worry about them again.

The biggest change you will notice is the refresh of new shocks, whether you get high end coil overs, springs and shocks or even just new OEM struts.

Edit: if you're really trying to improve stability, the extra you save on a shock/spring kit you could instead spend on sway bars, renewed bushings or put it towards the LSD.

[bradsm87]

My plan is this stuff for now:
MFactory LSD
M3 front lower control arms and tension arms
M3 rear subframe bushes
E93 M-sport 15mm rear swaybar


When I have more cash handy:
Bilstein B12 spring/shock set
M3 rear guide rods


The car has a very noticeable understeer tendency from factory. Adding front camber by running M3 control arms and removing the strut top locating pins as well as running the thicker rear swaybar should balance the car to my liking.

I plan increase front camber to 1º45' for decreased understeer and more outright cornering grip and reduce rear camber to 1º15' to improve traction. Hoping to fit it all in one go next weekend.

[LotusBMW]

Originally Posted by bradsm87

My plan is this stuff for now:
MFactory LSD
M3 front lower control arms and tension arms
M3 rear subframe bushes
E93 M-sport 15mm rear swaybar


When I have more cash handy:
Bilstein B12 spring/shock set
M3 rear guide rods


The car has a very noticeable understeer tendency from factory. Adding front camber by running M3 control arms and removing the strut top locating pins as well as running the thicker rear swaybar should balance the car to my liking.

I plan increase front camber to 1º45' for decreased understeer and more outright cornering grip and reduce rear camber to 1º15' to improve traction. Hoping to fit it all in one go next weekend.

Well, very interested to see how this all turns out for you. Not least of all the diff. Do I take it you've got the non M-sport suspension?

[bradsm87]

Originally Posted by LotusBMW

Well, very interested to see how this all turns out for you. Not least of all the diff. Do I take it you've got the non M-sport suspension?

I have M-Sport suspension. For non-M-Sport suspension, Bilstein B12 would be first on the list for me.

[Kiwi Peter]

Here is a break down on my car, suspension wise
2007 E92 Steptronic

front
1 M3 lower arms
2 M3 tension arms
3 M3 tower bar
4 H&R sway bar
5 Adjustable sway bar links
6 BC ER coilovers

Rear
1 M3 subframe complete with bushes etc
2 M3 arms all
3 M3 E93 sway bar
4 M3 LSD and 3.85 ratio
5 BC ER coilovers

Setup
Front toe 0mm
Rear toe 2mm in
Front camber 2 degrees neg
Rear camber 1 degree 30" neg

Ride height with 19" wheels from rim edge to the guard
Front 590mm
Rear 590mm

Shock settings front
Bump 4 clicks
Rebound 8 clicks

Shock settings rear
Bump 3 clicks
Rebound 9 clicks

And i still use the run flat tyres, with non run flat tyres the shock settings would be different, a few clicks firmer

Conclusion
I have owned many high performance cars both race and road, with this setup its towards the top of my list it is so planted, and the drive out of turns is second to none. Yes this is a road car, track day setup is different.

Hope this info helps some of you

[LotusBMW]

Thank you Peter. I'll take a good look at that info next week. I've spent 8 hours in my car today and in my opinion the suspension is easily the worst aspect of the car. Cheers.

[Kiwi Peter]

Originally Posted by LotusBMW

Thank you Peter. I'll take a good look at that info next week. I've spent 8 hours in my car today and in my opinion the suspension is easily the worst aspect of the car. Cheers.

Totally agree, some of the cars i drive at work are scary they wallow, sway and crab walk all over the place. sometimes i get out of these cars and just shake my head, all this power and no way to harness it.

My advice to many is do not turn off DST until you get things sorted.

[LotusBMW]

^^ Would agree with this. It's usually the first thing I do in a car (turn TC off) but at no point did I feel compelled to do this yesterday. M Sport suspension is clumsy.

• Feel like the suspension is trying to control lead weights instead of wheels
• It bounces all over high frequency bumps
• Larger dips are handled OK
• It is effective in that I could hustle the car quite quickly (nothing tight mind you) but it is not a thing of joy
• Rear 'sway' is definitely apparent via the subframe
• Its noisy and uncomfortable

My outgoing Mazda6 has suspension the 335i would die for. Really subtle well judged dampening control and it just feels very right

There is some work to be done to get all of this right.