[raceyBMW]

I did them on my E34 which was similar...though in the E92 there are two more. Its all about having the right bushing puller tool, otherwise you will have a bitch of a time with them.

[cpt97m3]

Originally Posted by sappersix

Orb, thanks for weighing in. I had been avoiding the subframe because of labor cost, but maybe I'll need to do it. I'll give myself a bit more drive time on the new setup before making more changes.

BTW, I just ordered my Bentley shop manual. Could a mechanically minded, but weekend warrior mechanic do an R/R of sub-frame bushings?

I did mine (135i, but same procedure) in my garage. I posted a write-up and some pictures over in the 1 series suspension section. It's a little time consuming, but very doable at home. I highly recommend them also. The car behaves more solid now.

[specE30Dude]

Originally Posted by Orb

It will not be possible to correct any instability with the rear suspension when you increase the spring rate or added a stiffer sway bar (it is not going to get any better not matter what!!!!). The explanation is simple….think about how load is transfer to one member at time and you see that the reaction forces at the sub frame will take a chunk of the load and not the spring. I think I was the first to discover this back over 3 years ago…remembering TC Kline was thinking I was nuts running a spring over 500 lb/in on the rear. Tuning the suspension was a complete failure until I upgraded the sub frame bushing and front tension strut. As for upgrading the valving, it should not be necessary considering the motion ratio and your current suspension frequency. The dampener only cares about frequency not spring rate. The dog tracking or side to side motion is due to the OEM rear toe links and front tension struts. You not are going to get a real smooth ride with mono tube dampener with washer stacking valve system. Discrete compression valving for high low speed is a bear minimum. If you dropped the car more than 0.8” then you might as well forget tuning or raise the car back up. The car should be dropped evenly front and rear. Bump stop length should be about 45-50 mm for the rear and 30-35 mm in the front with the softest possible material. The isolator on the rear dampener are not huge issue but changing the bottom ones to M3 setup does help correct over and under shoot in transient conditions.

Orb

Orb - Thanks for your feedback. It makes sense. It appears that the rear subframe bushings are a priority. I would like to do this myself but it may be a PITA with the diesel (urea tank,etc.). I have already completed the front M3 links. I am still running stock sway bars.

I have time for my final review as I just heard my wheels are going to be another 5wks..which I can understand being that they're coming from Japan. When those are on, I will attempt to adjust for the best street performance ride height.

Any thoughts on how the lighter wheels/tires (50+lbs less of unsprung weight) will impact the geometry/feel of the Swift/AST setup?

I also spoke with Harold yesterday and shared with him that my confidence and appreciation for the ride gets better everyday. I pay very close attention to detail and my initial feedback was more in comparison of the stock ride - As Orb pointed out, its clear that the increased spring rates are exposing the soft rear subframe bushings.

[1&done]

Originally Posted by sappersix

Orb, thanks for weighing in. I had been avoiding the subframe because of labor cost, but maybe I'll need to do it. I'll give myself a bit more drive time on the new setup before making more changes.

BTW, I just ordered my Bentley shop manual. Could a mechanically minded, but weekend warrior mechanic do an R/R of sub-frame bushings?

You can DIY. It looks harder than what it is. I am in the process of doing mine right now. Rent the bushing tool from Harold. PM me if you have questions or need advice.

[f00dstamps]

I performed some custom work so I can be able to easily adjust the rear shock rebound settings.

cover on

cover off

close up

[HP Autosport]

Originally Posted by f00dstamps

I performed some custom work so I can be able to easily adjust the rear shock rebound settings.

cover on

cover off

close up

That is one of most inovative damper adjustment access mod I have ever seen. Good job!

[f00dstamps]

Harold - Thanks for the compliment. When I purchased my 4100's from you, the adjustment extenders were out of stock. I drove with my trunk liner out of my car for a couple of weeks until I had some time to implement my idea. I wanted it to look stock but still allow me to easily adjust the settings. They are just 2.25" grommet hole covers designed for a computer desk.

[HP Autosport]

Originally Posted by f00dstamps

Harold - Thanks for the compliment. When I purchased my 4100's from you, the adjustment extenders were out of stock. I drove with my trunk liner out of my car for a couple of weeks until I had some time to implement my idea. I wanted it to look stock but still allow me to easily adjust the settings. They are just 2.25" grommet hole covers designed for a computer desk.

Once again, great work! It looks very oem like.

[1&done]

Originally Posted by f00dstamps

I performed some custom work so I can be able to easily adjust the rear shock rebound settings.

cover on

cover off

close up

nice job, I went w/ the flex-adjusters...like your idea better...and it was less $

[sappersix]

f00dstamps, well-modded...

I just went with the traditional adjustment extenders and a wee slit in the liner, but now I have computer desk grommet hole cover envy...

[tibra1]

Originally Posted by skinrock

Tell me about it. I have suspension on the way and plan on taking it to SonicMS. I also have an LSD sitting here, going to have MPT install it.

+1

OSG LSD and m3 arms, sways and bushings sitting in my room..waiting on my swift/ast from Harold to come in..i went w the 4200s..from what i have read thus far ASTs are amazing

[tibra1]

Originally Posted by HP Autowerks

Some of the bounce you guys are feeling are in the oem lower damper saddle, it's all rubber, the upper rebound and compression cushions are of a soft rubber foam material doesn't help the situation either. The deflections in these components aren't being controlled by the dampers at all.

Many choose to upgrade to the M3 rear lower camber links, that will take care most of the bounce. Then there is the M3 rear subframe bushings, but at 7 hours or so labor many will choose not to do it.

Doing the rear subfrm bushings and the rear camber link w an m3 shock for this reason.

[UltraRacer13]

just ordered me some grommets! f00dstamps = genius!

[NiVeDh]

For those with these coilovers, is the highest possible height still lower than ZSP?

[UltraRacer13]

I just wrote this to a PM asking if I adjust my vorshlags at the track. The answer is yes- here is how I was told to do it by AST/Vorshlag

There is a kick ass write up I found on this ( see link below)- plus I spoke with Brian from AST about it (and the vorshlg guys). Basically set the car up for the street with camber toe you want. Be sure your shop places the bolts through the strut tower brace all the way inboard. There is some play, so if they just set them in the middle, you won't be able to replicate the setting after adjusting the plates. This is huge. Have them align according to your parameters and bolt everything down (inboard). Then mark your plates with a black sharpie on the scale. This is your baseline street setup.

Then have your shop loosen the bolts and adjust your plates to your desired track setup (I am going with -3 deg, but still tweaking) Then mark your plate with a red sharpie. (again, be sure they have the bolts 100% inboard, only the plate has changed.) This will result in a bit of toe out, but that is fine. Now , when you go to the track, you can jack up the car and easily adjust these yourself, and then afterwards, go back to your original setting. Simple!

Here is the post by Terry Fair (Vorshlag) explaining this much better-
http://forums.bimmerforums.com/forum...ight=alignment

AST Tuning Guide
http://www.vorshlag.com/documents/Tuning_AST_Shocks.pdf

[f00dstamps]

Anyone noticing a popping/thumping noise from their front suspension at low speeds (<25mph) like me? Do any of you have a solution to my problem?

[specE30Dude]

Originally Posted by specE30Dude

In case anyone was curious what the current height described by my last post looks like, I've attached a photo that was taken today. I hope to have the new wheels/tires by the end of the month and will post more then.

Also, additional feedback from a drive this weekend through some great twisties up to the top of the Shenandoah Mtns. The suspension felt VERY good and planted going in and coming out of the turns under heavy breaking driving at 95% of what the tires would allow. Clearly, a huge improvement from stock. With that said, the road was recently paved and no bumps whatsoever.

After the new tires/wheels are installed and ride height is adjusted a bit more (slightly higher), I will provide more feedback.

3 Months later and I get somewhere! The new tires and wheels have been installed and I have now had several months on the suspension. I could not be more happy with representing the "D" as a special street car.

As far as the suspension goes, it is due for more tweaking, unfortunately. My 450/800 setup remains to be far too much for stock subframe bushings when the suspension is forced to travel (over bumps) at high speeds. It just doesn't feel as stable as a I like - I will be investigating more when I can find the time to do the install.

I was previously running stock BMW 195 wheels with run flats and my new set up is below:
Advan RS (Gunmetal) F, 18X8.5 - 235/40/18 R, 18X9.5 - 265/35/18
Michelin Pilot Super Sports
>>I could not be happier with the look and fitment! The tires feel much better than the RFTs but that doesn't change that the suspension is still stiff with a very light wheel setup. Gunmetal goes very well with Space Gray. Comparing the numbers, I have lost 56-60lbs of unsprung weight, not including the weight lost by the Swift/AST setup.

Other Mods:
>> Switching between Burger Tuning Diesel Module and the VAC Tuning Box. Both are roughly the same with slightly different setup/claims but they both put a smile on my face.. I may sell one of them?
>> Front M3 wishbone and tension links
>> Black kidney grille
>> 35% window tint on all side and rear windows.

Still to go near term:
>> Sub frame bushings and other rear links. Probably will start with sub frame only.
>> Front strut bar
>> M tech front bumper

Pictures - I hope to be taking better much ones soon:

[tibra1]

Originally Posted by f00dstamps

Anyone noticing a popping/thumping noise from their front suspension at low speeds (<25mph) like me? Do any of you have a solution to my problem?

Did you ever work this out..am interested to hear whats going on there.

[Fraggy]

Originally Posted by sappersix

Orb, thanks for weighing in. I had been avoiding the subframe because of labor cost, but maybe I'll need to do it. I'll give myself a bit more drive time on the new setup before making more changes.

BTW, I just ordered my Bentley shop manual. Could a mechanically minded, but weekend warrior mechanic do an R/R of sub-frame bushings?

Yup jzepeda just did it and then some

http://www.e90post.com/forums/showthread.php?t=543188

[rogerdiaz]

Originally Posted by specE30Dude

3 Months later and I get somewhere! The new tires and wheels have been installed and I have now had several months on the suspension. I could not be more happy with representing the "D" as a special street car.

As far as the suspension goes, it is due for more tweaking, unfortunately. My 450/800 setup remains to be far too much for stock subframe bushings when the suspension is forced to travel (over bumps) at high speeds. It just doesn't feel as stable as a I like - I will be investigating more when I can find the time to do the install.

I was previously running stock BMW 195 wheels with run flats and my new set up is below:
Advan RS (Gunmetal) F, 18X8.5 - 235/40/18 R, 18X9.5 - 265/35/18
Michelin Pilot Super Sports
>>I could not be happier with the look and fitment! The tires feel much better than the RFTs but that doesn't change that the suspension is still stiff with a very light wheel setup. Gunmetal goes very well with Space Gray. Comparing the numbers, I have lost 56-60lbs of unsprung weight, not including the weight lost by the Swift/AST setup.

Other Mods:
>> Switching between Burger Tuning Diesel Module and the VAC Tuning Box. Both are roughly the same with slightly different setup/claims but they both put a smile on my face.. I may sell one of them?
>> Front M3 wishbone and tension links
>> Black kidney grille
>> 35% window tint on all side and rear windows.

Still to go near term:
>> Sub frame bushings and other rear links. Probably will start with sub frame only.
>> Front strut bar
>> M tech front bumper

Pictures - I hope to be taking better much ones soon:

How is the suspension going. You did the install yourself? Diesel owner here also, i am going more conservative since i dont track...bmw oem perf with m3 front bits.

[f00dstamps]

Originally Posted by tibra1

Did you ever work this out..am interested to hear whats going on there.

The collar on the front passenger coilover that connects to the sway bar was loose. Once I tightened it, the noise went away.