Opinions on Poly VS OEM and check my suspension refresh list please

[Kimber]

I've been planning to refresh my suspension on my '06 auto vert I got last year with roughly 95k miles. I plan on keeping this car for a long time (10+ years) and don't see myself tracking it ever. I only drive in the summer months, and about 5k a year. Just spirited driving. I'm trying to get the best handling I can get out of the car without losing too much ride quality (aren't we all )

I'm also planning on going to a square wheel setup in the future (maybe end of summer after my DWS wear out, fronts are good, but rear's are getting close). Not sure if I will try to find 2 stock wheels, or go with something like the APEX wheels with Michelin PSS. (Probably the 18" Apex)

I got in as a tester for the new YCW/Mfactory coilovers. You can see the actual pictures of them on page 3 of this thread.

I am going to rent the tools from elcid86 and I have a mechanic friend that owes me a favor and he is helping me do the install of everything (he has a lift!! )

In a couple days I'm having him check out tie rods and front ball joints to make sure everything is good and I don't need to replace anything there.

I also have sourced a OEM front sway bar from a M3 vert (so it's 27mm).

Here is my list (I linked them all to help anyone in the future as well):

Powerflex Rear Diff Rear Bushing : PFR5-4626

Powerflex Rear Diff Front Bushings : PFR5-4625x2

Powerflex Rear Subframe Rear Inserts - PFR5-4613

Powerflex Rear Subframe Front Inserts - PFR5-4614

Powerflex Front Sway Bar Bushings : PFF5-4602-27x2

Powerflex Rear Sway Bar Bushings : PFR5-504-20x2

BimmerWorld Rear Trailing Arm Bearing Kit

OEM BMW front reinforcement plates

ECS "vert specific" rear shock mount reinforcement plate set

Lemforder Rear sway bar links

Lemforder M3 Rear trailing arm ball joints (4 of them)

Lemforder M3 engine mounts

OEM M3 trans mounts (says manual, but I'm assuming the auto is the same)

FCAB OEM Z4M bushings

I have the Powerflex rear subframe inserts in my list to save a couple bucks over the AKG set that would have been quite a bit more. I'm wondering if anyone has experience with these Powerflex inserts and if they are worth the savings of roughly $100 over the AKG set. The Powerflex street version is 70A compared to the AKG set which is 95A. (powerflex does have the race version which would be 95A as well)

The differential bushings were my other question. ECS sells a nice set and would be 88A compared to 80A for the powerflex street version I have in my list. ECS is a little cheaper. Does anyone have any experience with either of these brands or recommend using something different?

And I am pretty sure I was going to go with the OEM Z4M FCAB's, but was looking for people's opinions as well on this area.

So I hope you guys can chime in on what you have, and what you like or dislike about the parts, etc.

Also if you see anything you think I am missing please let me know. I want a complete list so there is no delay in getting everything installed at one time.

Thanks in advance guys!

[sillieidiot]

i was too lazy to read, so I just skimmed really fast. But do you have sway bar endlinks on your list? or is it included with the coils? You might need that. I saw that you listed rear, but not front. I would recommend some adjustable endlinks in case they don't fit with your coils.

[Kimber]

i was too lazy to read, so I just skimmed really fast. But do you have sway bar endlinks on your list? or is it included with the coils? You might need that. I saw that you listed rear, but not front. I would recommend some adjustable endlinks in case they don't fit with your coils.

Yes the coilovers came with adjustable endlinks, so that's why I didn't put them on the list, but good catch!

[ryankokesh]

I went with AKG over power flex, but I can't imagine there's a noticeable quality difference. I'd be comfortable going either route.

[Karl Lazlo]

I went with AKG over power flex, but I can't imagine there's a noticeable quality difference. I'd be comfortable going either route.

Same. Did AKG 95A diff and subframe, and FCABs on a recent refresh of my 03 ZSP. Deciding factor for me was that while the PF FCABs lasted longer than the OE, they ate themselves in a shorter dwell time (~60k) than what I had hoped. Overall, I am very happy with how the car tracks and responds to throttle adjustments.

The added bits I have installed: RE RTABs, RE strut brace, RE RSMs, M3 rear control arm bushings, M3 motor and trans mounts, OE F upper strut mount with plates, PF sway bar bushings, OE end links, Bilstein HD with stock (sport) springs. All on ET35 18x8.5 shod with Mich PSS 255 section width squared.

No noise from the suspension, but may be a little "harsh" for some people, but I have commuted to NYC with this car plenty of times, doesn't bother me... It does tramline more than my ZHP that has a more "tame" suspension and staggered wheels/tire. But, I attribute the tram-lining of the ZSP to the square setup, slightly wider track and stiffer sidewalls of the PSS compared to the softer Connie ECDWs on the ZHP.

[KevinC]

My indy put some kind of poly bushings in my FCABs a couple of months ago, and I HATE them with a passion. Steering is twitchy on-center now, after being perfection before with stock bearings (at least before they were shot).

[ryankokesh]

My indy put some kind of poly bushings in my FCABs a couple of months ago, and I HATE them with a passion. Steering is twitchy on-center now, after being perfection before with stock bearings (at least before they were shot).

That's interesting to hear, I haven't experienced anything similar. Just out of curiosity, did he show you the alignment sheet afterwards?

[Kimber]

Same. Did AKG 95A diff and subframe, and FCABs on a recent refresh of my 03 ZSP. Deciding factor for me was that while the PF FCABs lasted longer than the OE, they ate themselves in a shorter dwell time (~60k) than what I had hoped. Overall, I am very happy with how the car tracks and responds to throttle adjustments.

The added bits I have installed: RE RTABs, RE strut brace, RE RSMs, M3 rear control arm bushings, M3 motor and trans mounts, OE F upper strut mount with plates, PF sway bar bushings, OE end links, Bilstein HD with stock (sport) springs. All on ET35 18x8.5 shod with Mich PSS 255 section width squared.

No noise from the suspension, but may be a little "harsh" for some people, but I have commuted to NYC with this car plenty of times, doesn't bother me... It does tramline more than my ZHP that has a more "tame" suspension and staggered wheels/tire. But, I attribute the tram-lining of the ZSP to the square setup, slightly wider track and stiffer sidewalls of the PSS compared to the softer Connie ECDWs on the ZHP.

Seems pretty close to what I have planned. When you say "harsh" what are you describing?

I'm not a racer, and doubt I will ever track my car, I just want the best handling I can get without having to kill the ride quality. (I lifted my 4runner and although it looks bad ass and can climb over anything, the on road ride quality is no where near the stock ride. I wouldn't change it because it's my hunting/winter truck, but for my car, I'm hoping to have a nice quality ride.)

Do you get any rubbing with your tires? That is actually about the same square set up with PSS's I was thinking of switching to later this year. I like the wider look of tires.

[Sockethead]

Same. Did AKG 95A diff and subframe, and FCABs on a recent refresh of my 03 ZSP. Deciding factor for me was that while the PF FCABs lasted longer than the OE, they ate themselves in a shorter dwell time (~60k) than what I had hoped. Overall, I am very happy with how the car tracks and responds to throttle adjustments.

The added bits I have installed: RE RTABs, RE strut brace, RE RSMs, M3 rear control arm bushings, M3 motor and trans mounts, OE F upper strut mount with plates, PF sway bar bushings, OE end links, Bilstein HD with stock (sport) springs. All on ET35 18x8.5 shod with Mich PSS 255 section width squared.

No noise from the suspension, but may be a little "harsh" for some people, but I have commuted to NYC with this car plenty of times, doesn't bother me... It does tramline more than my ZHP that has a more "tame" suspension and staggered wheels/tire. But, I attribute the tram-lining of the ZSP to the square setup, slightly wider track and stiffer sidewalls of the PSS compared to the softer Connie ECDWs on the ZHP.

Did the poly diff bushings tighten up the drive line slop you get when shifting hard?

[slater]

Did the poly diff bushings tighten up the drive line slop you get when shifting hard?

that and stiffer trans mounts. mine is smooth - power on when you hit the gas, power off when you release. no delay or slop.