Horrible ride quality and can't figure out why
 

So I'm out of ideas on why my ride quality is pure garbage and hoping you guys can help me out...

Here is my setup:

- BR series BC Coilovers (NON true rear) - Dampers set to FULL SOFT
- Swift coilover springs in the fronts at 10k (same rate as the default springs on the coilover kit)
- Hotchkis Front Sway bar
- NO rear sway (have hotchkis installed but currently not connected to one endlink)
- Z1 rear camber arms
- 20mm Z1 hub centric spacers in the rear
- Only lowered enough to eliminate the wheel gaps, but not tucking at all and only had visible negative camber in the rear before my alignment.

I can't imagine the ride quality im experiencing is normal. I've got the dampers set to full soft and im not running stiffer springs than what the kit comes with (10k Front/8k rear on the divorced spring). Spring preload is separate from ride height on this kit, and was installed properly.

Before my alignment I was getting bad darting/tramlining from the rear toe being off pretty bad. As you can see, the camber is still not in spec, but only out of spec by .3 degrees in the rear and .8 degrees in the front. Even with the adjustable camber arms installed, toe can't be dialed in if camber is, and vice versa, so I obviously opted for toe to be in spec for now.

The car doesn't dart around *as much* anymore but I still feel a ton of instability when going over certain bumps at certain speeds. Nothing crazy, just regular street driving.

I know coilovers are naturally stiffer than stock struts, but I'm still feeling a lot of energy transfer into the body of the car and its borderline unbearable.

Before the coilovers, I had swift lowering springs with stock struts and it pretty much felt identical to stock ride quality if not better. I'm about to pull the trigger and just revert back to that setup but I'm still unsure if the there's a different culprit here. Could the amount of negative camber be the entire reason for the instability over most uneven surfaces? If it is, do I just need to get adjustable traction arms to let them get BOTH the rear camber and toe in spec?

The car feels fine when going over forgiving larger bumps, but its the smaller jagged divots and pot hole type imperfections that it absolutely hates.

Here are the final Alignment Specs:

http://www.the370z.com/attachment.ph...1&d=1609283231

...is BC supposed to ride like stock...?

First of all, you alignment is jacked up. Camber is no where close and the toe is horrible. Toe should be set to dead middle of spec for front and rear. The next question is what spring rates did you get?

... um no....

what I'm trying to figure out is if coilovers are supposed to ride like ****

I was not happy about the toe either, but the "tech" told me I'm fine as long as its in range and the 7/100ths of a degree wouldn't be noticeable.

Camber on the other hand is obviously out of range, but its not even visible, and I've driven cars with worse negative camber before that did not feel as bad as this. I understand every car is different though so if I can be convinced that getting everything green will solve my problems I'm willing to chase that result. The question is what parts will I need to allow it? My spring buckets are still housing the springs so I don't think I can get actual toe arms, which leaves me with the traction arms but I've heard that they shouldn't be used to adjust the toe. I also don't think aftermarket eccentric toe bolts will do the trick either but that's just a guess.

You need SPC toe bolts to get the rear Toe in spec with the proper camber. Excessive camber will cause the Tramline to be worse. You need front camber arms or FUCA. Get SPL, they are easy to adjust. Set the camber to -1.4 front and -1.5 rear. As I said before, set the toe to dead middle of spec. The next thing to do is to properly setup the dampers. You want the dampers to control the compression and rebound. Full soft does nothing. You have to dial the dampers in to absorb those impacts. Set it in the middle and adjust until the car is more stable on a bumpy road. If it is still bouncing around, add one more click positive to make the dampers work more. It takes time to dial in the dampers. I tuned mine in on I-16 which is bumpy as hell. The ride is just about perfect now.

Where are you in Florida. If you can drive up to the Savannah, Ga. area I can set them up for you in about 30min. once you get the alignment set properly.

PM and ask Elmo370z how my car rides. It is easy to set them up when you get the hang of it.

This is super encouraging and it definitely gives me hope. What I still don't get though is if all these extra parts are needed to get coilovers to sit and feel right, how the hell is everyone else thats just running them alone getting away with it? The only explanation would be I'm too low which is causing all the negative camber, but I'm almost maxed to the highest setting in the rear and the fronts are probably just a tad lower than lowering springs which is like 1.5 - 2 inch drop.

Definitely going to look into some upper control arms and the toe bolts in the mean time, thank you for the direction!

South east coast but I'm almost willing to take a trip just to see what a tuned suspension is actually supposed to feel like on this car lol.

I actually had no idea the damper settings were actually meant to fine tune the ride quality. I always assumed stiffer = track, softer = street.

oh, a thought I just had was worn out or damaged control arm bushings in the rear where the spring bucket and shock connects to the rotor. I must have removed and reinstalled the entire suspension about 8 times already and the the bushings that the bolts go through may have potentially gotten worn or damaged. Just guessing though, I don't have any other reason to think they're messed up. Would the symptoms of that potentially cause what I'm feeling?

These specifically...

http://www.the370z.com/attachment.ph...1&d=1609297321

crap on a stick, the spc bolts require cutting the hole bigger. I have no idea who to trust to do that right around here :icon14:

Where do you live on the east coast. Maybe someone could recommend a shop. You really need to have the car corner balanced to get the most out of your new suspension.

You can do it with a Dremel tool. I believe you get a template with the toe bolts.

The damper are to absorb unwanted energy. What you will feel in the car is a bounce when you hit a rough spot. You want to tune that bounce out by stiffening up the damper setting so it can absorb that energy. It will dissipate it as heat. So in the summer time, you may have to run one more click on the dampers because the fluid is warmer. Your ride may be a little stiffer but the end result is a more compliant car that sucks up those bumps with no bouncy feeling. That intern keeps the wheels on the ground providing more traction.

^^^^^ this

I'm in greater fort lauderdale area. I wouldn't mind going as north as west palm beach, or as south as miami.

yeah, I'm just worried about messing up since its the actual subframe I'm cutting away from. Unless a lockout kit would be able to fix a hole that 's too big or not exactly the correct shape?

But wait a second, are you guys telling me that every single Z that's on coilovers at the very least needs to get FUCAs, rear camber arms and spc toe bolts if they want to get their alignment in spec and/or get their ride quality right? And based on it being due to the lower ride, wouldn't this apply to lowering springs too ? would I be able to avoid all this if I just raised the car about half an inch ?

As far as why other people never have issues? I have no idea. Maybe they are not in tune with what their car does. Some folks just can't tell they have an issue. If you are all the way down in Miami, that is a long *** trip of 9hrs. If you are in Jacksonville, it is 3hrs to me.

That would be a yes on lowering springs. You can slide by but it won't be close to spec and tire wear can get ugly quick depending on the toe settings. I am very funny about my alignment settings, I can't stand a darty car.

I honestly am very glad you understand what I mean and are saying this because I really can't understand how anyone would think this ride quality is acceptable, let alone expected to be performant.

I just watched a video on the spc toe bolt elongation and it doesn't look too bad, but I still rather avoid cutting the subframe if I can. Is there really no other way to get my alignment in spec without using the spring bucket arm to adjust the toe? I know they make adjustable traction arms but what exactly does that adjust and why can't I use those instead?

I do still have the true rear bc kit that I swapped out for the oem style, and if I put that back on, I would just need to replace spring buckets with adjustable toe arms, but **** man, there's gotta be an easier way to do this. Z's are known for there great handling and here I am literally hating the way it handles :crying:

It takes time and patience to get a car with coilovers setup properly. It's not cheap either.

You don't want to mess with adjusting the traction arms unless you want to change the rear geometry angles. If you don't know what you are doing, you just opened up a can of worms. Alignment shops have no clue about them. People replace the traction arms because they want to get rid of the rubber bushings.

yea I had a feeling that was the case, thanks for confirming.

I feel lost at this point. I either dump close to another grand on control arms, proper spc toe bolt installation, and alignment, hoping the end result is what I've been spending months trying to figure out, or going back to stock ride height and struts.

I'm still super surprised that every single lowered z has this issue and either doesn't know about it or spends thousands on tuning it properly. There's gotta be a way around it. I'm about to go raise it until the camber is at least in range but with my luck I'll be back at stock ride height :(

Comparing my factory Nismo suspension to the one I have now is night and day difference. I wish I would have spent more money on the dampers to make it even better. Overall, I am very happy with it.

Here is my old thread.

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

See, hearing that your setup is actually better than the nismo suspension gives me hope. I need that in my life.

I also see that you're an SPL whore so it makes a lot of sense why your ride is fantastic lol

That being said, to balance cost and effort in fixing my issues, I'm now leaning on going back to the true rear kit, SPL fucas, SPL camber arms, and SPL toe arms since the SPL mid links cost more than the entire coilover kit itself. The Z1 street edition cambers arms I have right now are literally pure garbage and I'm surprised they're even selling those creaky attic sounding pieces of ****. Can't wait to take them off.

Now to figure out where to get all this stuff at a good price lol.

Thanks for pointing me to your build thread, I'm looking forward to reading the whole thing.

If have 2 weeks straight to read you can look into my other one.

http://www.the370z.com/forced-induct...ports-228.html

What rear springs do you have on your truetype coilovers. They need to be much less. 5-6k springs.

Thread on True-Type coilovers.

http://www.the370z.com/track-autocro...coilovers.html

reading this thread is making my head hurt

There's no way -2 camber the cause of "horrible ride quality." I have Aragosta coils with 14/10 rates (middle settings all around), full SPL arms, factory bushings, and 20 inch wheels, my ride quality is absolutely fine.

I've had other people, non Z people drive and ride in the car, zero complaints. Its firmer than stock but bumps and road imperfections are well managed. This is with street specs running much lower than a track car would, as its geared towards appearance . . . and its still fine

Refer to the factory specs here and the rear camber isn't even off by that much:
http://www.the370z.com/brakes-suspen...ent-specs.html

There is no way to adjust front anything without adjustable arms. There is minimal adjustment in the rear. For optimal alignment, you need all three rear arms and a competent alignment tech

I don't know how much reading you did, clearly not enough. I personally have posted endlessly that that anyone with coilovers MUST get adjustable arms, with the SPL ones most recommended because they never break, they're easy to adjust ON CAR, and they have manufacturer support.

What i do not see addressed in this thread are your tires. What tires are you running, what size, and what is the condition?

this is an absolute must read as it explains why true type rears require roughly half the spring rate as non-true/divorced type

I dunno how many times i gotta tell people not to get Z1 and to get the ******* SPLs

do it right the first time or don't do it

There was a black Friday sale when SPL had all their stuff on sale. I posted about it. This is what happens when people don't listen to me

Contact some of the vendors here. I used ImportPartsPro, they had the best price

https://www.importpartspro.com/

He was talking about the car darting. Not really ride quality. Excessive negative camber causing tramlining to be worse. I knew what he was talking about. Guess you didn't pick it up. Chill out, he is trying to learn.

I've got 5k swifts on the true rear kit. I'm fully aware of how the wheel rate is about .5 to 1 on a Z and the oem springs are basically double the rate for the same feel as a true rear strut spring.



yeah, I was hoping to hear something like this. the front and rear toe is in range of manufacturers specs, and camber is only off by tenths of a degree which makes it hard to believe just that alone would cause so much instability over regular street imperfections. I'm just not experienced enough to be confident that its just the alignment at fault here. But, then I'm also not sure if you guys that are running the aragostas (which are almost 3 times the price) is the reason you aren't complaining about ride quality. But BC is super popular in the community so I also can't imagine they are the reason either.

I'm running stock tires all around. Got the car brand new back in June and I still only have 3k miles on it lol. BUT..... since I spent a ton of time trying to settle on a setup I liked, I drove around without an alignment enough to chew my tread down pretttttty bad. I know I know, but in a way I'm almost glad I'll be able to get rid of these crap tires soon. Here's the current status:

Stock Bridgestone Potenzas
Front: 245/40/19 @ 40-50% tread and 32psi
Rear: 275/35/19 @ 10-15% tread and 34psi


EDIT: yes, as Spooler pointed out, the instability im talking about is mostly darting and tramlining where the car kind of jolts to the side following a weird bump in the road or going over painted lettering that's slightly raised on the road will even cause me to grip the wheel hard to maintain a straight drive which blows my mind. I may actually go snap some pics of some bumps I know cause this pretty badly to give you guys an idea of what I mean. This is all at normal driving speeds too, nothing crazy.

yup, fully aware of this. My oem kit I currently have on is at 8k that came with the bc kit, and the true rear kit I had before this was using a 5k swift.

I'll admit I was in a rush to get something to allow me to align the car (its my dd) and couldn't really understand just by quickly skimming the descriptions, photos, and feedback why there would actually be a difference. Clearly I was wrong. Lesson learned.

FWIW, I noticed my car came from the factory with some strange findings...

I picked it up from a dealer with only 7 miles on it so I doubt they messed with it, BUT....

1. The front sway bar studs were over torqued and borderline stripped, because when I removed the nuts on one side, they were VERY loose. Reinstalling the sway caused them to fully strip and I had to drill them out and replace them with bolts.

2. the bolt that goes through the midlink on one side of the car was oddly deformed in a way I've never seen before. Here it is compared to the one from the other side for you guys to scratch your heads at...

http://www.the370z.com/attachment.ph...1&d=1609358122

:icon14: :eek: :shakes head:

That bolt was way over tightened so bad it stretched. WTH

I think you learned a lesson or two about suspension components, but haven't we identified the problem right here?

Dead tires are going to have a MUCH greater affect than one degree or less of camber of fractions of a degree in toe

aint no coilovers, arms, or alignment thats gonna affect your car more than not having tread

yeah I honestly have no idea how it could have happened, especially from the factory. surprisingly it caused no issues at all when it was installed, just super ******* weird when I saw it

I really really really hope this is what it is, or at least most of the reason. I would really love to know and understand the technical reason for it though. Like how does a 100% tread tire cause the car to not dart around as much? does the softer rubber absorb some energy when it happens? does a balder tire act like a stiffer wheel?

EDIT: I was able to measure about 2-3mm of remaining tread on the rears and about 4 or 5mm on the front. I don't know what the original tread depth was but I'll assum its a centimeter, so that would technically mean I'm at 20-30% in the rear and 40-50% in the front but not sure if that really makes a difference

So far this is my plan of action...

- switch back over to true rear coilovers
- get SPL front upper control arms
- get SPL rear toe Arms
- replace Z1 camber arms with SPL camber arms
- new tires
- another alignment
- stop complaining

I know its a super debatable topic, but are my upper strut mount studs really at risk with true rear setup? They're welded to the chassis and if they ever snapped or stripped, I feel like I'd be ******. I also can't imagine theres a noticeable difference in handling even though that's the common rumor but still curious what you guys have to say about it.

True type makes for easier spring rate calc and adjustment precision.
If math is done correctly, and shocks and springs properly matched, there’s no handling difference.