Best suspension for Daily Driver / Backroads Dancer 135i

[tjswarbrick]

Hi guys (and gals, too!)
Can you stand another one of these "best suspension" threads?
I think I know what I want to get out of it, at least.

I've driven a number of e46 and E90 3'ers, and they just seem to flow over the road. My E88, not so much. It is sublime top-down at speed on the right (curving, smooth) roads. But around town on the unrepaired roads I seem to travel often I get these harsh, jarring hits and sometimes a snap or loud cracking sound. While I do what I can to avoid potholes, these road imperfections go nearly unnoticed in my wife's Pathfinder and were just a minor inconvenience in my previous W203 C230. And the 328's/330's/335's I've driven just take them in stride. I like to drive my wife, friends, and kids around - but a jarring, jostling ride makes it no fun for them. And I fear for the long-term structural integrity of the vehicle the way it sounds. Sometimes it just doesn't seem all that BMW-like to me.

However, I also want to firm up the suspension for those times when the going gets fun. Some body roll is great for feel and progressiveness, but as we all know the stock 135i M-Sport suspension leaves a bit more than necessary on the table.

My 1'er is not a race vehicle, but I hope to take it to CCC, Auto-X, and maybe a couple track days a year. Mostly I want it to feel and perform at the highest level bombing down the awesome but not always meticulously maintained backroads available in my area.

I suspect a great deal of the impact harshness can be laid at the feet of the fun-flat tires. So as soon as they wear out, I'm getting Michelin Pilot Sports. Probably 225/40 up front and 245/35 out back with M3 sway bar, likely Dinan camber plates, and some RSFB's to tame the slop, roll and understeer a bit.

I have 12mm spacers, under the stock 261 wheels, which seem to have helped the tiniest bit. I plan to keep them unless clearance becomes an issue. I'm not looking for huge drop - just 1/2 to 3/4" lower than stock M-Sport seems ideal to me, but the 1" lowering of Swift's springs is right in the ballpark as well. Once I get the damping set to my liking, I really don't plan/expect/want to change it for conditions or environment.

Now, on to my real issue.

How do I improve the handling to something comparable to a 1g-capable E30 M3, while making it ride like an E39 M5 or E90 335i Sport Pack?

I thought I was going to go Koni Yellow's over Swift Springs, but the more I read the more I see that's really a compromise for great handling and acceptable ride at a very competitive price. I want less compromise.

Just received word that I am getting a little bonus this year. Hooray! So I can splurge a little and get a set of $2k-range coilovers.

I read a (single) review here which said that (IP-issues and long-term longevity aside) the CA-Tuned coilovers ride much better than the Yellows/Swifts - so that's got me thinking to go with coilovers.

Fairly common wisdom says that ST XTA's and KW-V1's ride well, but their damping and progressive-rate springs make their on-track handling rather suspect. I once followed a guy with a FBO E82 with ST's, M3 control arms & MPSS on some of our best roads. I could basically keep up with him, but I was working REALLY hard and my passenger got rather motion-sick.

I don't love the idea of the progressive springs on the KW-V2, but otherwise they seem like a good compromise package.

Reading the write-up on the 128i I long for the TC Kline coilover setup. Harold at HP said I should go with 350# front and 600# rear springs for a Cabrio street car.
Swift R-SPec's are 201# front / 502# rear. Will the TCK setup (single-adjust) be able to compete from a ride standpoint? And if I go TCK, which springs are likely to offer the least compromised ride without giving anything away in handling?

Should I look at Ohlins or Bilstein?

What's my best bet to optimize handling (grip, composure, feel, response, progressive breakaway) and driving enjoyment improvement as I can in conjunction with the very best ride in a 135i convertible in an under $2500 springs/shocks or coilover setup?

Thanks!

[CRYA]

Whoah good question. I'm in the same boat. Looking forward to replies although my budget is much less!

[asbrr]

This is funny, I was planning on writing up a big thread in the same vein. I have a 128i coupe, but looking for opinions on a good daily driver setup that tightens things up, doesn't slam the car (I drive year round), and is still supple on the small bumps but good body control when things get hairy.

I've been thinking of:

BMW Yellow Perf springs + b6 or b8 bilsteins
BMW Yellow Perf springs with koni yellows
BMW Yellow Perf springs with koni white TCK single adjust shocks
Bilstein B12

Or some other spring combo with the above?

Sorry OP, not trying to hijack the thread, just interested to hear what people have to say....I'll be starting my own thread separately

[CRYA]

Originally Posted by asbrr

This is funny, I was planning on writing up a big thread in the same vein. I have a 128i coupe, but looking for opinions on a good daily driver setup that tightens things up, doesn't slam the car (I drive year round), and is still supple on the small bumps but good body control when things get hairy.

I've been thinking of:

BMW Yellow Perf springs + b6 or b8 bilsteins
BMW Yellow Perf springs with koni yellows
BMW Yellow Perf springs with koni white TCK single adjust shocks
Bilstein B12

Or some other spring combo with the above?

Sorry OP, not trying to hijack the thread, just interested to hear what people have to say....I'll be starting my own thread separately

Can BMWP yellow springs be mixed and matched that way? I didn't know that and was seriously looking at their whole kit. But getting the springs alone is an interesting idea.

[tjswarbrick]

I do wonder how the BMW PS springs compare to the Swift Spec-R's over a given set of shocks.
Aren't they something like 1/2" drop compared to M-Sport and 160 lbs/in front and 420 lbs/in rear?
May still be kinda soft...

[swagon]

I have had KW V2's since August 2015 and have not had any issues with them so far. (fingers crossed)

We have very bad roads here and the way they soak up the road imperfections at higher speeds is just great.

The next step is definitely subframe bushings (or inserts) and maybe lower control arms; then I think it will be perfect for my needs.

You'll probably not need all the adjustment (rebound & compression) on a street car, but since yours is a cab there might be issues with the ride height because of the weight of the car - there are no E88-specific springs on the market and most of the aftermarket springs give 135i's too much positive rake. Depends on whether you want to dial in the perfect ride height, too.

Turner lists Bilstein B16 PSS10 for $2022 which almost fits your $2k budget. I would consider those.

My 2 cents... I am definitely no expert in this field.

[Gangplank]

Originally Posted by CRYA

Can BMWP yellow springs be mixed and matched that way? I didn't know that and was seriously looking at their whole kit. But getting the springs alone is an interesting idea.

From what I've read in the suspension section write ups they can. B6 & B8 have the same dampening but the B8 is lower.

[swagon]

Originally Posted by Gangplank

From what I've read in the suspension section write ups they can. B6 & B8 have the same dampening but the B8 is lower.

Yes, it has a shorter body. 30mm difference I think.

[Gangplank]

Swagon any thoughts on the KWs vs Billys in ride comfort?

I'm considering the KW V1 but don't want to get much drop...

[Nicklv_m3]

My car is my daily and aggressive street driver, what I did was Bilstein B12 Pro Kit, Whiteline rear subframe bushing inserts and ECSTuning 28MM solid front sway bar... Paired with APEX EC-7 wheels.. 18x8.5, 18x9.5 wrapped in 225/40, 265/35 Michelin PSS. The car rides SOOO much better!! Handles amazing now! Feels much more planted driving around and much more confident in the corners. Doesn't have that stock floaty feeling anymore. Car launches better thanks to tires and RSFB inserts... It's perfect. I didn't feel a need for Coilovers on this car.

[swagon]

Originally Posted by Gangplank

Swagon any thoughts on the KWs vs Billys in ride comfort?

I'm considering the KW V1 but don't want to get much drop...

What kind of Bilsteins?

I would not bother with the KW V1's. They are not a quality kit from what I have heard.

My V2's, set up as high as possible, actually raised the ride height although they claim a 15mm min. drop.

Originally Posted by Vegas135i

My car is my daily and aggressive street driver, what I did was Bilstein B12 Pro Kit, Whiteline rear subframe bushing inserts and ECSTuning 28MM solid front sway bar... Paired with APEX EC-7 wheels.. 18x8.5, 18x9.5 wrapped in 225/40, 265/35 Michelin PSS. The car rides SOOO much better!! Handles amazing now! Feels much more planted driving around and much more confident in the corners. Doesn't have that stock floaty feeling anymore. Car launches better thanks to tires and RSFB inserts... It's perfect. I didn't feel a need for Coilovers on this car.

Yup, the B12 is a great bang for the buck. Got any pics of the car?

Can't wait to get it installed on another BMW in two weeks, hopefully.

[tjswarbrick]

Based on reading previous reviews and such I really hadn't considered the Bilsteins - but it looks like the B12 kit may be up to the task.

Anyone have experience with B12/Eibach vs Yellow/Swift? I'd love to get impressions from someone who's tried both.

Would pairing the B8 shocks with the Swift springs be worth looking in to? Or that likely to be too stiff for the street. (If I understand correctly, B8 has firmer damping than Yellow, and Swift is a stiffer spring than the Eibach - but possibly higher quality, and linear instead of progressive. But I could be wrong.)

Thanks Guys!

[CRYA]

Just FYI thanks to Vegas for finding the site with the best price on the B12 kit. That site currently has it on sale for below $700 if anyone is interested. PM me.

[jafo1701]

Originally Posted by tjswarbrick

I do wonder how the BMW PS springs compare to the Swift Spec-R's over a given set of shocks.
Aren't they something like 1/2" drop compared to M-Sport and 160 lbs/in front and 420 lbs/in rear?
May still be kinda soft...

I ran BMW performance with Koni Yellows. On the street they were fine, but I found them lacking on the track. I switched over to the Swifts, not wanting to go with a full coilover set. Swifts feel a lot stiffer despite the only slight increase in spring rate. I also should be noted that I run most of the M3 suspension parts that will swap over. I am very happy with the Swifts and Konis.

[Gangplank]

Does the B12 lower the car at all? I might consider the B12 w/ BMW Perf. springs or swift springs. Hmmm....

[tjswarbrick]

Originally Posted by jafo1701

I ran BMW performance with Koni Yellows. On the street they were fine, but I found them lacking on the track. I switched over to the Swifts, not wanting to go with a full coilover set. Swifts feel a lot stiffer despite the only slight increase in spring rate. I also should be noted that I run most of the M3 suspension parts that will swap over. I am very happy with the Swifts and Konis.

jafo - with Swifts feels a lot stiffer in cornering, over patchy pavement, or both?

Originally Posted by Gangplank

Does the B12 lower the car at all? I might consider the B12 w/ BMW Perf. springs or swift springs. Hmmm....

I'm no expert - particularly on the Bilsteins. I'm just starting to figure those out.
If I am understanding correctly:
It looks like the B12 Sportline lowers 30-50mm (1.25-2 inches), and the B12 Pro Kit lowers 30mm/1.25".
B8 is the shock used in the B12 kit - so those are what you want if you're going to do other springs. I saw one mention (on an Audi or Mazda site, I think )that B6's and B8's are valved the same but B8's are already 30mm lower. Not sure how that would affect use of Swift or PS springs with either set of Eibach shocks.
Honestly, that's the main reason I hadn't considered the Bilsteins before - too many choices, with not enough information.

Personally, I'd be happy with 15-25mm lowering.
I hadn't thought about them since reading a 135is review that said the ride was harsh. Maybe I should consider Perf. springs with a set of shocks. Wonder how they'd do over TCK's White version of the Koni Yellow's???

[Turbmando]

I'm also looking to upgrade my suspension. I'm heavily considering 2 options.

1. Full BMW Performance Suspension

Lots of reviews on this site. Just a few.
http://www.1addicts.com/forums/showthread.php?t=403757
http://www.1addicts.com/forums/showthread.php?t=711513
http://www.1addicts.com/forums/showthread.php?t=466597

2. BMW Performance Springs with Bilstein B6 Shocks/Struts

Good review.
http://www.1addicts.com/forums/showthread.php?t=1116635

[tjswarbrick]

Originally Posted by Turbmando

I'm also looking to upgrade my suspension. I'm heavily considering 2 options.

1. Full BMW Performance Suspension

Lots of reviews on this site. Just a few.
http://www.1addicts.com/forums/showthread.php?t=403757
http://www.1addicts.com/forums/showthread.php?t=711513
http://www.1addicts.com/forums/showthread.php?t=466597

2. BMW Performance Springs with Bilstein B6 Shocks/Struts

Good review.
http://www.1addicts.com/forums/showthread.php?t=1116635

Awesome!
Thanks for the links.
I was just searching for that last one but hadn't had any luck finding it.

[swagon]

Originally Posted by Gangplank

Does the B12 lower the car at all? I might consider the B12 w/ BMW Perf. springs or swift springs. Hmmm....

Originally Posted by tjswarbrick

If I am understanding correctly:
It looks like the B12 Sportline lowers 30-50mm (1.25-2 inches), and the B12 Pro Kit lowers 30mm/1.25".
...
I hadn't thought about them since reading a 135is review that said the ride was harsh. Maybe I should consider Perf. springs with a set of shocks. Wonder how they'd do over TCK's White version of the Koni Yellow's???

Substract 15 mm from the Pro Kit. M Sport suspension is 15 mm lower than the standard which the measurements (and most likely the suspension kit) are based on. 30-35 mm=15-20 mm in case of 135's. However, expect more since the 135's have a heavier nose than other 1 Series variants.

Eibach Sportlines are not available for the 135i.

BMW Performance springs have a guaranteed 10mm lowering since their springs are different for each model and you give BMW your VIN code I think.

Koni Yellows & PS are a proven combo over at the E90post, too. The struts are adjustable.

Performance shocks, Dinan springs ( 3002 tii 's ex):





135i's on Bilstein B12 (Bilstein B8 shocks + Eibach Pro Kit springs):









Oh crap, I just remembered: NO PERFORMANCE SUSPENSION FOR CONVERTIBLES

[tjswarbrick]

Originally Posted by swagon

Substract 15 mm from the Pro Kit. M Sport suspension is 15 mm lower than the standard which the measurements (and most likely the suspension kit) are based on. 30-35 mm=15-20 mm in case of 135's. However, expect more since the 135's have a heavier nose than other 1 Series variants.

Eibach Sportlines are not available for the 135i.

BMW Performance springs have a guaranteed 10mm lowering since their springs are different for each model and you give BMW your VIN code I think.

Koni Yellows & PS are a proven combo over at the E90post, too. The struts are adjustable.

Performance shocks, Dinan springs ( 3002 tii 's ex):


135i's on Bilstein B12 (Bilstein B8 shocks + Eibach Pro Kit springs):

Oh crap, I just remembered: NO PERFORMANCE SUSPENSION FOR CONVERTIBLES

It's kind of a unicorn but isn't there an E88 135is? I swear I've seen two around here somewhere.

I forgot about the Dinan springs. I'll probably get their camber plates and those guys are local so maybe I'll check it out. Wonder if they'd work best with B6's, B8's or Yellows.

[HyeWarrior]

Sub'd to read up later

[Esteban]

Originally Posted by tjswarbrick

It's kind of a unicorn but isn't there an E88 135is? I swear I've seen two around here somewhere.

I forgot about the Dinan springs. I'll probably get their camber plates and those guys are local so maybe I'll check it out. Wonder if they'd work best with B6's, B8's or Yellows.

OP, just to let you know, the Dinan springs for the 135i currently don't show up (at least when I look) on Dinan's website. Don't know if that's an error or if they've been discontinued. Maybe give them a call if you're interested.

Also, in case there's any confusion, a convertible 135is was made, but it came with the M Sport suspension like the standard 135i convertible and not with the BMWPS. As swagon said in his post above, the BMWPS was not intended for the 135i and 135is convertibles.