Upgrading 135is Rear Bushings / Front Control Arms - Suggestions Needed

[mjack]

I've been doing research on the best route to tighten up my suspension after adding my eibach lowering springs and I'm hoping to get suggestions with this thread.

I read through both the threads at the top of this section about front and rear control arms upgrades and came to the conclusion that it seems only the front arms are worth upgrading and that the rear subframe bushings are the best upgrade for the rear.

As of now I am planning on buying both of these kits:

Rear bushing kit: https://www.ecstuning.com/b-assemble...3326763092kt1/

M3 front control arms kit: https://www.ecstuning.com/b-trw-part...1102283577mkt/

Should I buy that entire rear bushing kit or I should I only buy the subframe bushings by themselves?

I received an install quote from my local shop, they said $1000 total in labor to install both kits if I provide parts. Is this reasonable?

I am pretty green when it comes to suspension work/tech so please bear with me

[Ric in RVA]

The rear bushing kit is overkill.

Do whiteline inserts, whiteline bushings or just the M3 bushings.

Replacing the front control arms is one of the easiest things you will ever do on this car.

Look up threads to see how it is done. Final tighten on the ground!!!!

Get an alignment.

[asbrr]

Originally Posted by jack135is

I've been doing research on the best route to tighten up my suspension after adding my eibach lowering springs and I'm hoping to get suggestions with this thread.

I read through both the threads at the top of this section about front and rear control arms upgrades and came to the conclusion that it seems only the front arms are worth upgrading and that the rear subframe bushings are the best upgrade for the rear.

As of now I am planning on buying both of these kits:

Rear bushing kit: https://www.ecstuning.com/b-assemble...3326763092kt1/

M3 front control arms kit: https://www.ecstuning.com/b-trw-part...1102283577mkt/

Should I buy that entire rear bushing kit or I should I only buy the subframe bushings by themselves?

I received an install quote from my local shop, they said $1000 total in labor to install both kits if I provide parts. Is this reasonable?

I am pretty green when it comes to suspension work/tech so please bear with me

$1000 for installing ALL the bushings and control arms is not unreasonable, it's a lot of work.

I would just add that your stock factory shocks are not great, and you should probably upgrade them to something like a Bilstein B8 or Koni setup that will better match the Eibachs. It would be a shame to spend $1000 and still have factory shocks...

[mjack]

Originally Posted by Ric in RVA

The rear bushing kit is overkill.

Do whiteline inserts, whiteline bushings or just the M3 bushings.

Replacing the front control arms is one of the easiest things you will ever do on this car.

Look up threads to see how it is done. Final tighten on the ground!!!!

Get an alignment.

I was kinda hoping someone would tell me that entire kit was overkill. Unless there is real benefits to replacing those other bushings, I'll just go with the M3 bushings. Thank you.

Originally Posted by asbrr

$1000 for installing ALL the bushings and control arms is not unreasonable, it's a lot of work.

I would just add that your stock factory shocks are not great, and you should probably upgrade them to something like a Bilstein B8 or Koni setup that will better match the Eibachs. It would be a shame to spend $1000 and still have factory shocks...

I believe the 135is has M shocks from factory? I could be wrong

[Suprgnat]

Originally Posted by jack135is

I believe the 135is has M shocks from factory? I could be wrong

M-Sport.

There is a difference.

[Esteban]

Originally Posted by jack135is

I believe the 135is has M shocks from factory? I could be wrong

All 135s, whether it is a 135i or a 135is, come with the same shocks from the factory.

As Suprgnat indicated above, they are the shocks that are included in the M Sport suspension.

[asbrr]

Originally Posted by jack135is

I was kinda hoping someone would tell me that entire kit was overkill. Unless there is real benefits to replacing those other bushings, I'll just go with the M3 bushings. Thank you.

I believe the 135is has M shocks from factory? I could be wrong

Not many have done the full bushings, most will do the rear subframe ones and call it a day, I thought you were being bold in doing all of them

Yes as others have said, the "sport" package suspension is the same as the "m-sport" package suspension and is what comes on all 1 series cars if optioned that way (including 135is). The M Performance suspension is an upgrade available separately from BMW.

I would recommend you add beefier shocks either from the M Performance suspension or other quality aftermarket brands like Bilstein, Koni etc.

[mjack]

Originally Posted by asbrr

Not many have done the full bushings, most will do the rear subframe ones and call it a day, I thought you were being bold in doing all of them

Yes as others have said, the "sport" package suspension is the same as the "m-sport" package suspension and is what comes on all 1 series cars if optioned that way (including 135is). The M Performance suspension is an upgrade available separately from BMW.

I would recommend you add beefier shocks either from the M Performance suspension or other quality aftermarket brands like Bilstein, Koni etc.

Who knows, maybe I will do the full bushing set

Sounds like the general consensus is I should get some new shocks too. I'm just looking to upgrade slowly but surely.

[Suprgnat]

Originally Posted by jack135is

Who knows, maybe I will do the full bushing set

Sounds like the general consensus is I should get some new shocks too. I'm just looking to upgrade slowly but surely.

Do something to firm up the rear toe arms. Either bushings or aftermarket arms.

[135ivert]

Originally Posted by jack135is

Who knows, maybe I will do the full bushing set

Sounds like the general consensus is I should get some new shocks too. I'm just looking to upgrade slowly but surely.

The point to remember is that there are some economies to be had by doing multiple tasks at once. Like "while you're doing X, it also makes sense to do Y." Ask your shop or the experts here what to do at the same time.

[John_01]

If your car is a 2013 model and not travelled unusually high mileage, it seems a bit too soon to be replacing every bushing.

Both the shocks and rear subframe bushings are major weakness, so you might as well have the work done at the same time. Especially if you are installing M3 front arms. You should save on the workshop time and you don't need to go back and forward to the wheel alignment shop after every step.

If you get the rear subframe bushings installed by a shop you will probably pay quite a lot no matter which rear bushings are used. I would say the M3 rear subframe bushings are an excellent quality and very durable option. It would be a pity to install some polyurethane part that will later start squeaking, degrade or crack.

[mjack]

Originally Posted by Suprgnat

Do something to firm up the rear toe arms. Either bushings or aftermarket arms.

Are these the rear ones worth upgrading? I had read a thread about how most of the rear arms really weren't worth upgrading. Also having a hard time finding some aftermarket or M3 quality ones for my car for some reason.

Originally Posted by 135ivert

The point to remember is that there are some economies to be had by doing multiple tasks at once. Like "while you're doing X, it also makes sense to do Y." Ask your shop or the experts here what to do at the same time.

This is a fair point. I think what I will have done first is the lowering springs + front control arms at the same time. Then in a couple months I'll go back for shock install once I decide on which ones to go with.

[mjack]

Originally Posted by John_01

If your car is a 2013 model and not travelled unusually high mileage, it seems a bit too soon to be replacing every bushing.

Both the shocks and rear subframe bushings are major weakness, so you might as well have the work done at the same time. Especially if you are installing M3 front arms. You should save on the workshop time and you don't need to go back and forward to the wheel alignment shop after every step.

If you get the rear subframe bushings installed by a shop you will probably pay quite a lot no matter which rear bushings are used. I would say the M3 rear subframe bushings are an excellent quality and very durable option. It would be a pity to install some polyurethane part that will later start squeaking, degrade or crack.

The problem I am having with the subframe bushings is that all the shops are quoting me labor which includes them removing the entire subframe. I have found the DIYs where the subframe only needs lowered. I think I will DIY the subframe and then take the car in to have them install shocks + alignment. I agree on the M3 bushings too, definitely going that route.

[asbrr]

Originally Posted by jack135is

..snip...

This is a fair point. I think what I will have done first is the lowering springs + front control arms at the same time. Then in a couple months I'll go back for shock install once I decide on which ones to go with.

Maybe you misunderstood - but the issue with going back to do shocks later is that you're adding up on labour. Take the front for example. In order to replace the springs you have the take the strut assembly apart. That means the shock is basically "out" already. Doing the shocks later means the strut will have to be taken apart again.

I'd just recommend doing more research now and deciding on shocks, so you do them at the same time. Bushings etc are mostly a separate labour item with not too much overlap of shock/spring install.

[Suprgnat]

Originally Posted by jack135is

Are these the rear ones worth upgrading? I had read a thread about how most of the rear arms really weren't worth upgrading. Also having a hard time finding some aftermarket or M3 quality ones for my car for some reason.



This is a fair point. I think what I will have done first is the lowering springs + front control arms at the same time. Then in a couple months I'll go back for shock install once I decide on which ones to go with.

I'm talking about the rear toe arms. That said, I think it's an extremely well designed rear suspension. It's basically a sophisticated double a-arm with toe compensation. The closer one can keep it to "ideal" specification is the key to precise handling and the trade-offs have been well discussed. fe1rx has researched this at length (and designed some gorgeous ///M inspired toe arms).

My take aways from all of this:

I have M wishbones, guide rods, camber arms, and Rogue toe arms. I'll take the combined weight savings of all the ///M rear components and they're a minor upgrade to overall stiffness and bushing compliance. I like the way they behave as as system, but have no objective data to back that up. ISTG, every time I limit bushing compliance my car gets more fun to drive. It's a curse. I swore I wouldn't do it this time.

For no good reason, I also think the rear trailing arm bushings have been (largely) ignored. They are an equal partner in the overall suspension geometry. I'm looking at Genuine Group-N rubber and/or various aftermarket spherical options, and have a rear hub lying around with which to design a bushing extraction/installation tool. It'll happen when it happens, if it happens. I promised my Dad I'd get back to the Healey.

Nah, I can do both!

BTW, the Rogue toe arms were installed at 4915 miles along with the ///M wishbones and guides, and now all have an additional 27336 miles on them and are going strong. I purchased upgraded spherical bearings years ago and have yet to use them. On the other hand the original "Seals-it" seals have done their job and need replacement. My car has relatively low miles, but no one would say they've been easy

[Suprgnat]

Originally Posted by jack135is

Are these the rear ones worth upgrading? I had read a thread about how most of the rear arms really weren't worth upgrading. Also having a hard time finding some aftermarket or M3 quality ones for my car for some reason.



This is a fair point. I think what I will have done first is the lowering springs + front control arms at the same time. Then in a couple months I'll go back for shock install once I decide on which ones to go with.

Oh, and as for the RSFBs, the ///M are great but, were I to do it again, I would seriously consider stiffer or solid.

[mjack]

Originally Posted by asbrr

Maybe you misunderstood - but the issue with going back to do shocks later is that you're adding up on labour. Take the front for example. In order to replace the springs you have the take the strut assembly apart. That means the shock is basically "out" already. Doing the shocks later means the strut will have to be taken apart again.

I'd just recommend doing more research now and deciding on shocks, so you do them at the same time. Bushings etc are mostly a separate labour item with not too much overlap of shock/spring install.

Excellent suggestion, thank you. I just spoke to the shop and they said it would be an additional $50 to add all 4 shocks at the same time as the springs.

They are quoting me $550 in labor to install all 4 m3 front control arms, eibach springs, the aftermarket shocks, and alignment. I think it seems like a very fair deal.

I am thinking about going with these shocks... mostly because my car is my daily and a 95% street car 5% track. https://www.ecstuning.com/b-koni-par.../21004036~kon/

Any other recommendations?

[asbrr]

Originally Posted by jack135is

Excellent suggestion, thank you. I just spoke to the shop and they said it would be an additional $50 to add all 4 shocks at the same time as the springs.

They are quoting me $550 in labor to install all 4 m3 front control arms, eibach springs, the aftermarket shocks, and alignment. I think it seems like a very fair deal.

I am thinking about going with these shocks... mostly because my car is my daily and a 95% street car 5% track. https://www.ecstuning.com/b-koni-par.../21004036~kon/

Any other recommendations?

Yes that's not a bad deal, and as you can see very little difference in extra labour for the shocks.

The FSD's are good for a smooth ride, and replacement for the stock shocks. With a stiffer and lower spring like the Eibach, my personal preference would be to look at something like the Koni Sport shocks (Yellow)
https://www.ecstuning.com/b-koni-par...rt/e9xkonispt/

Some folks have run the FSD for occasional track use - it's really about preference so do lots of reading/research on other peoples experience if you are not in a rush.

[a4nut]

So I'm working on the same issue for my IS, and I would not consider the FSDs. I have the FSDs on my e90, and they are better than the stock IS suspension, they just still like I'm driving my sofa. Mind you I came from a MINI, but I still prefer a more sporty ride, but still needs to handle the terrible roads here in Cincinnati...

[HP Autosport]

If this is to remain a street car, upgrade the front control arm and rear subframe bushings to M3 and you will get a night and day difference. There is no need to do the entire rear kit.

$1000 is really good for the amount of work involved installing all those bushings.

[mjack]

So I have decided to go with an ST Coilover kit as apposed to matching shocks/struts up with another brand of springs.

Next month I will be doing the m3 front controller arms and m3 subframe bushings, which I just won on an ebay auction for $115 for all 4 bushings.

Does this sound like a solid path? I have the same shop doing the installs and they warranty the alignment for 6 months, including if I bring it back for more suspension work.

[John_01]

ST coilovers have unusual spring rates where the rear spring rate is too soft relative to the front. It may have been a deliberate design compromise to accept the stock rear subframe bushings, which may not tolerate higher rear spring rates.

KW V2 would be a better choice from a performance point of view, but I'm concerned it may not ride as well as some of the possible combos using the BMW performance springs. Also if you go for Koni or KW style adjustable dampers you will have trouble to access the top adjust points due to the position of the stock strut reinforcement bar. It will also prevent the installation of the dust caps for the front strut bearings. 1M coupe strut reinforcement bar is a good solution to solve these issues, but costs some $.