Feedback request:Daily Driver complete suspension rebuild plan.
 

Hi,
I'm putting together a plan to rebuild the suspension on my daily driven 2014, MT, Z with the sports package. I'm the original owner, the car has 70K miles and it won't see the track...I just don't have time for the maintenance track driving requires. I like a firm ride and I've driven cars with poly bushings. I'm looking to improve OE performance and make the car handle better and more predictably.

Here's the plan:
Z1 Motorsports front upper control arms, traction and camber arms
Eibach Pro Kit 1" drop w/springs and sway bars
OE type front lower control arms with whiteline bushings
OE type rear upper control arms with whiteline bushings
Whiteline front and rear sway bar end links
Koni Yellows w/ OE type strut plate and shock bushings
Whiteline differential bushings
Eibach 15mm spacers x4

I might replace the LSD while this is happening, but that depends on funds.

Is there anything else in the suspension I need to replace? Do the rear lower control arms have inner and outer bushings as well? Should I replace the rear crossmember bushings as well?

Anyone done this?

Thanks, everyone.

Hector

If you want to know what you are going into. Here are my 2 threads on replacing the suspension bushings with the SPL catalog.

http://www.the370z.com/brakes-suspen...uspension.html

http://www.the370z.com/brakes-suspen...on-almost.html

As for replacing the rear sub-frame bushings. Believe you only have 2 choices. The solid SPL kit which replaces the bushing all together. And the Z1 kit which you install parts into the stock bushing. The Z1 kit is the one you want. It still has some flex in it unlike the SPL bushings.

I recommend doing the motor mounts, transmission mount, differential bushings, and Z1 subframe collars before touching your suspension bushings. The difference is big. Add performance oriented springs and you'll be in good shape.

What tires do you plan on using?

I don't recommend the Z1 front upper control arms. You may not even need them. If you do, they aren't adjustable once installed. So you basically hope that you get it right (camber and caster) before they go on. Its just not a good system. SPC came out with a different version of their FUCA's which are probably better for adjusting. I had Z1, now I have SPL FUCA's.

Thanks for the input. I didn't think about the motor and transmission mounts and I'd never even heard of those subframe collars. I watched the Z1 video and I'm impressed.

I'm going to use the Eibach springs. Are you suggesting those might not be a good match?

Do you commute in your car with solid bushings in it? I thought that would be super stiff.

Thank you. I'm glad someone else pointed that out. The Eibach rep I talked to said the same thing because the springs will lower the car less than an inch, but I thought I'd change them just in case they needed adjustment. I looked at the Z1 FUCA and compared it to the SPL part on the Z1 website. I see the issue you mentioned. You saved me a headache and I appreciate that.

I'll go with stock replacements. I'm still going to replace them but only because I'll have to pull them out to replace the bushings and I'll address the ball joint while I'm there.

Not sure yet, but a summer specific tread in the stock size. What's up?

rear toe bolts.

Eibach springs are good. They're not just lowering springs, and actually give a performance benefit. I have Swift springs, which are a bit stiffer and drop just a bit lower. If you can find some Nismo take off parts (dampers, springs [little to no drop], sway bars), those are usually a nice upgrade for a small price too.

I have taken the Z on a couple of long trips with no issues. Actually, it's not stiff. The stock rubber bushing bind the travel movement. For example, if you remove the front coil-over. With the stock rubber bushings. The spindle will stay put at about mid travel, and it's hard to move up and down. With the SPL bearings. The spindle will fall on it's own weight. You can pick it up and down with no problems. The SPL bearings make the suspension more responsive. They will increase the noise and vibes some what.

Thank you all for the feedback.

I'm unsure how many bushings are on the rear knuckle side and if anyone makes poly replacements. Does this look like a complete list of replaceable bushings?

Front upper control arms inner
Front lower control arms inner
Front sway bar
Front sway bar endlinks
Front upper strut plate
Engine mounts
Tranny mounts
Differential lower and center
Rear subframe bushings
Rear upper control arms
Traction arms forward bushing
Camber arms forward bushing
Rear lower control arm inner
Rear sway bar
Rear sway bar endlink bushings

How many are on the rear knuckle? Do the traction, camber arms and lower control arm have rubber bushings on the knuckle side?

thanks!

-H

There is 4 bushings on each rear knuckle. Traction arm, camber arm, mid link and lower shock. You have to remove the knuckle to replace the bushings. The mid link, traction and camber arms have no bushings on the side that mounts to the knuckle. They mount to the bushings in the knuckle.

Upgraded Rear Knuckle Bushings for 370Z and G37 | SPL Parts

There is no strut plate.

Chances are that you will have to drop the sub-frame to get to the rear upper arms. I haven't replaced those yet. That's an after Christmas project.

Rusty,

Thanks, man. I appreciate the replies and info. When I get all of this together I'll post the rebuild.

I thought for sure there was an upper strut plate with the studs that go through the strut tower? Am I getting the nomenclature wrong?

Did I get this right?

Just chiming in? Do you really need full bushing replacement at just 70k miles? driving habits are specific to car and owner but if this is a DD, i can't see how bushings are shot that fast.

This isn't really a quick/easy job, pulling the rear suspension, burning/pressing bushings out and replacing all of them is time/effort, even if you can do it yourself. Seems like kind of a pain in the *** to do all that for poly bushings on a DD - i could totally see dropping in spherical bushings everywhere for a track car.

To me this is a hard balance between replacing stuff with quality but expensive parts or just fixing what needs to be fixed.

SPL everything will make your car awesome, but its expensive. Like, really awesome. But expensive.

How bout scouring used parts areas for lower-mileage Z's that have had stuff replaced for aftermarket?

It's your time, it's your money, it's your sweat, i'm just pointing out maybe think about what you really need, the cost, and what you're actually getting for it all.

Going eibach/koni and OE style everything, seems like performance is a low priority, so . . . maybe save some money where u can?

Thanks for the input. All great points to consider. I'm the original owner of this car and it really does handle poorly. I consider this just wear and tear, but I want to be thorough in addressing it. Next Oct/Nov I'm going with some form of boost and I want to make sure the foundation is solid. Addressing the suspension, brakes, and rear are the first steps. The power is great, so I can address that later. The poly bushings (for me personally) are a great compromise between solid and OE. I've done this whole thing with an '86 5.0 years ago and the order of work just seems to make sense.

Other than the wear and tear, my Z is solid and she deserves another go. I won't be surprised if I see over 200K on this one.

At 70k miles you say it handles poorly. I doubt the bushings are the problem but the shocks are definitely ready to be replaced.

I have the Koni shocks and Eibach front sway bar and it made a big difference and I only had 30k on my Z when I swapped the shocks. My recommendation for adjusting the Koni shocks is to keep the rebound soft for the street if the roads are not perfect and keep the rebound softer in the rear then the front.

What you are seeing, is the upper mounting bracket for the coilover.

I think I would have to agree with optionzero on this one. At 70k I doubt your bushings are truly worn, more than likely it's your shocks (if anything, might just be you want more than what oem has to offer). Replacing all the bushings with poly for a DD and then staying with eibach springs and Koni yellows I'm just not sure the value in that. I believe powertrix just posted a sale going on in one of the other post as well as Fortune having a sale coming up. Either of those would be near the cost of 4 Koni yellow and eibach springs and will most likely make all the difference you'll want (the fortune run a softer spring though so may want to request stiffer). That and aftermarket bars will make a bigger difference than bushings and will probably still have less effect on NVH (or at least buzz).

Yeah if you want to improve handling, skip that spring shock nonsense


Fortune and powertrix coilovers
Better rubber
SPL front upper control arms for full camber/caster adjustment

And if u can do it, a diff upgrade. Wavetrac or OS giken

This would be your best bang for the buck.

Fortune/Power trix = $1300 (less if you get a sale price)
19 inch grippy tires = $1300
SPL FUCA = $900

Total = $3500ish

Totally streetable daily driver
MUCH more noticeable upgrade

Parts have re-sale value (especially the SPL FUCAs)