Weekend driving strut options

[ccdre]

Long story short, I had my car on the lift and noticed the passenger side rubber dust boot covering the strut rod is completely torn.
I'm guessing replacing it will require compressing the spring, removing the strut etc. - my car has whatever the stock suspension is on a 2010 135i with M sport package.

What would be an inexpensive upgrade for my struts/springs should I decide to swap them instead of just replacing the rubber dust boot?

I don't track the car, but do take it for spirited drives and twisty roads.

Lastly, do I need to replace the rear shocks as well to match characteristics of upgraded front struts?

I'm running 261 style wheels, non RFT (225/40r18 fronts and 255/35r18 rears) if that's a consideration.

Thanks and sorry if this was previously answered.

[HP Autosport]

We recommend Koni(adjustable) if you want to do this in steps to keep the damping somewhat close to OEM. You can keep the rear shocks until you are ready to upgrade them.

OEM springs are fine(they last a long time) unless you want to drop the car. Then BMW Performance springs will give you a 10mm drop, everything else is 25mm or more.

[asbrr]

Originally Posted by ccdre

Long story short, I had my car on the lift and noticed the passenger side rubber dust boot covering the strut rod is completely torn.
I'm guessing replacing it will require compressing the spring, removing the strut etc. - my car has whatever the stock suspension is on a 2010 135i with M sport package.

What would be an inexpensive upgrade for my struts/springs should I decide to swap them instead of just replacing the rubber dust boot?

I don't track the car, but do take it for spirited drives and twisty roads.

Lastly, do I need to replace the rear shocks as well to match characteristics of upgraded front struts?

I'm running 261 style wheels, non RFT (225/40r18 fronts and 255/35r18 rears) if that's a consideration.

Thanks and sorry if this was previously answered.

Its a slippery slope, I have a 2010 128i and did the exact kit mentioned by Washington335i (it's also called a B12 Kit from bilstein). Nice performance upgrade but still totally street usable. I did a refresh of all the small rubber parts at the same time, plus the addition of dinan camber plates, dinan rear shock mounts, and whiteline full subframe bushings.

You could forego the dinan and whiteline stuff and still have a very nicely upgraded car. But definitely replace the wear/rubber parts when doing it. ECS sells a full kit for like $250 which replaces all the various little parts. Called a suspension retrofit kit or something.

Tons of threads on this, search Bilstein B12, or there is a monster thread called "back roads dancer" in the suspension forum. Koni shocks and swift springs is another very popular option.

[ccdre]

Ok, thanks guys! Sounds like I have some decisions to make.

Last question on this - since it seems all of the aftermarket as well as the BMW performance setups drop the car by 10-25mm, is it even a viable option to keep original springs and use an aftermarket strut?

[asbrr]

Originally Posted by ccdre

Ok, thanks guys! Sounds like I have some decisions to make.

Last question on this - since it seems all of the aftermarket as well as the BMW performance setups drop the car by 10-25mm, is it even a viable option to keep original springs and use an aftermarket strut?

No problem.

Yes absolutely - you have a 135 so it already comes with "M-sport" springs. There are aftermarket suspensions that do not drop the car much more beyond what you have today - the B12 for example is only about a 10-15mm drop at most from where you are now.

If that is too much for you, you could simply replace the shocks - Bilstein makes 2 types, the B6 and the B8. The B8 is meant for lower suspensions, the B6 for what is closer to stock. Now there has been some debate on if the B6 is suitable for the M-sport suspension or if the B8 is better, there are examples of people running both setups with no issues so the standard M-sport springs are likely a nice "in between" and either the B8 or B6 would work. B8s are a bit cheaper.

Koni shocks would work just fine as well, they make a few different kinds (orange, yellow) depending on what you're looking for. BMW also sells a performance suspension kit, shocks, and optionally springs (which are even milder in drop than the B12 kit, likely 10mm max).

Lastly, keep in mind the springs are the cheaper component in the equation, shocks/dampers will cost more, so if you're looking for an upgrade in the handling department might as well do both....

Slippery slope as I said

[ShocknAwe]

OP:

Define inexpensive upgrade for me. There are plenty of affordable options out there, but need to know what your concept of expense is.

[ccdre]

I'd like to keep the cost somewhere south of $1000, the less I spend on it the better.
To be honest,I don't have an issue with the way my car handles but if I'm going to take things apart to replace the torn rubber dust sleeve, I feel that a slight upgrade would be logical at that time.

Originally Posted by ShocknAwe

OP:

Define inexpensive upgrade for me. There are plenty of affordable options out there, but need to know what your concept of expense is.

[ShocknAwe]

Originally Posted by ccdre

I'd like to keep the cost somewhere south of $1000, the less I spend on it the better.
To be honest,I don't have an issue with the way my car handles but if I'm going to take things apart to replace the torn rubber dust sleeve, I feel that a slight upgrade would be logical at that time.

In that case, stick with a Damper+Spring configuration, there aren't any good coils for under $1000 IMO.

I can't recommend Swift Spec-R springs enough. Most even drop you will get, light weight, and very compliant. Can pair them up with Bilstein or Koni dampers, bilstein will be a bit more firm at low speed as compared to the Koni, but the Koni you will need to fiddle with adjustments until you are happy with them.

Had a Swift/Bilstein setup for ~2 years, only switched for a coilover setup when it became clear to me that I wanted more control over my ride height without sacrificing performance for my local roads. Absolute best bang for the buck out there.

Link to my build thread, have a comment about them on the first page. http://www.1addicts.com/forums/showthread.php?t=1027934

[ShocknAwe]

BMW PS while a fantastic kit, has dampers tuned for RFTs. Performance springs are an awesome option, but I would still partner them with Koni Sport or Bilstein B6 dampers.

[Esteban]

Originally Posted by ChrisAW1M

I would highly recommend getting the BMW Performance Suspension as it's a whole kit, will be probably just under $1200 or so for the kit (shown below), springs, and upgraded front sway bar. You could probably take advantage of various coupons and holiday deals too to get it a little cheaper.

I used to have a 135 and had that installed and trust me, it's a remarkable improvement in both handling and ride quality, too, especially since you've already switched to non RFT. It's also covered by BMW's warranty too for 2 years or may slide in and covered under your CPO or bmw extended warranty if you have one perhaps.

It will provide a minimal drop, which is subtle, but nice, won't look slammed, and everything is all designed to work together as a cohesive system.



Another really good and popular option is to go with a koni yellow shock + swift r spec spring from HP Autosport. Should be slightly cheaper and may provide even better performance, though that doesn't seem to be atop your priority list.

Interesting.

[Esteban]

I have the BMW Performance suspension and like it as well.