[rolando316]

Hey Guys,

I have been doing research on suspension upgrades and have decided to make my first one be some ST coilovers.


When it's time to change the RFTs I will move to Michelin PSS. I am "planning" to stop at FBO (Cobb Stg 2+). I might go to the track/autocross at some point in the future but it will never be heavy use (couple of times a yr). I mostly want to keep it to spirited runs and to improve street traction as this is still my daily driver. I would really like to use M3 suspension components but am still a little lost on what would best fit my goals. So that leads me to my main questions...


- What M3 bits would I benefit most from?


- Is there anything I could/should do at the same time as the coilovers to avoid excessive wear? (e.g. camber plates)


- Anything to do at the same time to minimize labor costs?


Advice would be greatly appreciated!

[HP Autosport]

Originally Posted by rolando316

Hey Guys,

I have been doing research on suspension upgrades and have decided to make my first one be some ST coilovers.


When it's time to change the RFTs I will move to Michelin PSS. I am "planning" to stop at FBO (Cobb Stg 2+). I might go to the track/autocross at some point in the future but it will never be heavy use (couple of times a yr). I mostly want to keep it to spirited runs and to improve street traction as this is still my daily driver. I would really like to use M3 suspension components but am still a little lost on what would best fit my goals. So that leads me to my main questions...


- What M3 bits would I benefit most from?


- Is there anything I could/should do at the same time as the coilovers to avoid excessive wear? (e.g. camber plates)


- Anything to do at the same time to minimize labor costs?


Advice would be greatly appreciated!

Best return in performance on your money would be the M3 front control arms. Your car being a 2007, the thrust arm bushing might be worn anyway. Also get new upper strut mounts as those can be worn in as little as 10K miles in our experience and you are not paying extra labor to have these installed.

That is a good start.

[rolando316]

Thanks for the info! Since the upper strut mounts can go out so quickly, are there any other alternatives than the stock ones?

Also, any info on what alignment I could request after switching over to m3 front suspension parts?

[CJ421]

The M3 front control arms/tension struts will give you a little extra camber in the front in addition to improving steering feel. They are a solid upgrade.

If you could, save a bit and invest more in better quality dampers/springs. Look into a Koni Yellow (Sport) setup with Eibach or H&R Sport springs. Dampers and springs will yield the biggest gains in handling vs. any other suspension component.

Michelin PSS is an excellent choice in tire, BTW.

[rolando316]

Originally Posted by CJ421

The M3 front control arms/tension struts will give you a little extra camber in the front in addition to improving steering feel. They are a solid upgrade.

If you could, save a bit and invest more in better quality dampers/springs. Look into a Koni Yellow (Sport) setup with Eibach or H&R Sport springs. Dampers and springs will yield the biggest gains in handling vs. any other suspension component.

Michelin PSS is an excellent choice in tire, BTW.

I've heard nothing but good things about the PSS's so I can't wait to switch to them from the RFTs!

Just when I thought I knew what my first suspension mod was going to be...back to the drawing board

You have an awesome set-up CJ, any reason that you went with dampers/springs over coilovers? I'm really attracted to the ride height adjustability of the coilovers especially bc when I do get the tires, I will likely be going up to 19" and trying to go up in tire size from 225/255 so it would be nice to adjust if needed.

What kind of drop do you have on your set-up?

[CJ421]

Hey rolando, I maintained the stock ride height; it's a tiny bit lower in the front and a tiny bit higher in the back (slightly raked like the M3). It looks more 'stanced' than stock especially with the extra camber in front.

BMW designed the suspension to run at stock ride height and changing it throws off the handling characteristics. The rear control arms are almost horizontal as-is. One inch is the maximum drop (IMO).
It wasn't planned, but with my fixed-height setup and M3 suspension swap I was able to use M3 springs, which are wider (a good thing).

I run 235/265 size tires on OEM 19" wheels (no spacers); no rubbing and a nice square look. I don't have dedicated track wheels yet. If I did I'd probably go 255/265 on Apex wheels.

In your place I'd probably go for a coilover setup (note: 'coilover' isn't a magical term; we already have MacPhearson front suspension design aka coil-over; a spring coiled over the damper. 'Coilover' in enthusiast and marketing circles is adopted to mean matched damper+spring with adjustable ride height). Unfortunately I have little experience with most of the available coilover kits. I'd point you at Ground Control - their products are well made - and TC Kline. Both use variations of Koni-based dampers. Unless your front control arms are leaking, I'd leave them be and go right to dampers and springs with camber plates if you can afford them. Camber is the #2 tool behind good tires to improve cornering ability.

[HP Autosport]

Originally Posted by rolando316

Thanks for the info! Since the upper strut mounts can go out so quickly, are there any other alternatives than the stock ones?

Also, any info on what alignment I could request after switching over to m3 front suspension parts?

Right now, there is not much options out there. There is not a HD version that we know of.

As much front camber as you can with the stock upper mounts, 1/16" to 1/8" of total toe in. For the rear -2 in camber and 1/8" to 3/16" of total toe in, less if you have some M3 bits and toe arms.

[Chrisred]

Hey Harold, what toe/caster settings would u recommend for xi models? Same as i?

[HP Autosport]

Originally Posted by Chrisred

Hey Harold, what toe/caster settings would u recommend for xi models? Same as i?

Xi can use just a bit less toe, 0 to 1/16" total in will be fine and as much caster as you can.

[Chrisred]

Originally Posted by HP Autowerks

Xi can use just a bit less toe, 0 to 1/16" total in will be fine and as much caster as you can.

Front and rear same?

[rolando316]

Thanks CJ and Harold! Lot of really good info and options to consider.

Will do some more research and post up pics and a review when I make a decision.

[CALWATERBOY]

Originally Posted by rolando316

Thanks CJ and Harold! Lot of really good info and options to consider.

Will do some more research and post up pics and a review when I make a decision.

You cannot have top performance without a LSD, M rear subframe bushings, and M sways or equiv.

For max saving, you can do what I did....be prepared for a major effort! Reward commensurate.

Recommend stock power until suspension/drivetrain's improved.