Swift springs + stock shocks = Awful ride?
 

I recently modified my G37S by adding swift springs and eibach sway bars. I’m loving the drop and the way the car drives on smooth roads but I’ve got to admit that the ride is fairly awful on roads with even some bumpiness or undulations. Hitting bumps on the road is pretty jarring. I am running on the stock shocks with 22k miles. I’d really like to keep the improved handling and more responsive feel of the car but want to improve the ride quality. FYI this car is my DD and will likely never go to the track. I’m thinking I have 3 options here:
1. Get Koni Yellows to replace stock shocks
2. Give up on the swifts and go with KW V1s
3. Go back to stock springs and shocks
I’ve heard great reviews around here and other forums about the swift and koni yellow combination but I’m not sure how nicely it rides or if it will help with my ride quality complaints. I’m also not experienced in suspension setups so I don’t know if I trust my ability to properly tune the shocks to get the optimal balance between performance and ride quality. On paper the KW V1s seem like a good idea for a daily driver since I can only change the height and the spring rate and dampening is preconfigured by KW engineers for a nice balance between sportiness and comfort.

Which of the above options would you guys suggest? Any help would be greatly appreciated.

IDK, my ride was way better with the Swifts and stock shocks. Bumpier, yes because of the stiffer spring rate, but no bounce or lack of rebound with the stock shocks...

Maybe a difference with the stock equipment on the G versus Z.... :ugh:

I don't seem to have much bounciness, but hitting some bumps feels more harsh than just stiff/firm. I've ridden in some cars slammed on springs with completely mismatched shocks that felt far worse but I've also been in cars with suspensions that somehow balanced performance and comfort more effectively too.

going with kwv1s might not solve your problem as it's only height adjustable i.e. *not* damping adjustable. it may be that you're a bit sensitive so I would suggest getting something that's more adjustable than not work from there (konis or coilovers that are at least 2 way adj)

Can you soften up the sway bars and see if that does the trick? I would do that first and see what happens.

I'm going with the kw v1's I have the swifts and stock shocks now..the kw v1 should be a much smoother ride. Ill know soon

First time I heard sombody complain with this combo!
Best ride feel ever better than stock is all I can share.

The sways in the front are already on the softest setting, the rears are in the middle. I think putting the rears on soft might bias the car more towards understeer but it might be worth trying.

I'd be curious to know how this turns out. What do you think of the ride quality of the swifts on stock shocks?

Maybe the roads where you live are really smooth? My car feels fantastic as long as I'm on a nice road but hitting a bump or undulation in the road at good speed feels pretty harsh for me with the current setup. I've definitely seen cars handle those bumps better. It might have been excessive to call the ride "Awful". It is livable and performs well on smooth roads but there is a lot of room for improvement on rough surfaces.

I think I will either go for Koni yellows or just go with the KW V1s. The KWs have progressive springs which should make the ride better but at the same time the linear swift springs feel very predictable. hmm :confused:

Im sorry man that your not quite happy with the current ride of your G with this springs but even on bumps and dips on the road I find the rebound comfortable and composed with the swift. I regretted selling mine just because I went to coils for more aggressive drop.

Have u tried checking your tire pressure? How many miles or how long have you been using the springs? You need to give it time to settle before you get yourself an alignment.

How many tread life do you have on your tires? Check it.
Maybe you need to change it since your at 22k now with oem tires?..,for a DD this should be close to be just about time to be replaced?
If your riding with Bridgestone OEM tires they are one of the noisiest and harsh ride ever. I changed mine to Hankooks. Man Im like a fat lard on a hammock.

Try checking this options before you change to coils or Koni's and see if it does makes a difference.

I'd be curious to know how this turns out. What do you think of the ride quality of the swifts on stock shocks?[/QUOTE]


when I hit a bumpy road I lose confidence in this setup, it doesn't feel like the shock can keep up. The kw v1 spring and shock should be setup to work better and handle the bumps better. Plus I get to go a little lower!

I really don't know how you drive your Z but I think Im pretty aggressive with the way I drive my Z...never had such issues you guys experienced.

Well possibly as far as I know FL has one of the best roads in the US.

I'm curious if it's a bump steer or alignment issue rather than a spring/shock issue.

Just I suspect too. Thanks for the input.

Good ideas. I will check the tire pressure. I've been on the springs for maybe 3 weeks, 500 miles. Still using the OEM Bridgestones and yes they are loud and harsh. They still have some life left but are on their way out. I was thinking about v12s but will probably go for PSS instead.

Pretty much same feeling for me. Hitting a bump, especially mid corner really takes away my confidence. Seems to really upset the balance of the car, like the car doesn't stay glued to the road. Suspension doesn't seem to really soak up any bumps.


I had an alignment right after the springs were installed. The rear camber is pretty off and the springs have settled since I did the install. I will be installing SPL rear camber arms and SPC toe bolts and re-aligning in a couple days.

Try to check as well if the springs are properly installed.
That figures without those camber and toe bolts your toe setting must be really off and your camber must be out of line too.

FirstbTry to find a good shop that could properly align your car.
Make sure your toe setting is at least close to zero. Caster set to max.

Front camber -1.4 and rears at -1.6 to -2 you should be within specs.

Change your tires to. Im running v12's 305 rears.
Seriously my Z is like on rails. But i do have white lines sway bars too.
I have invested a lot of my money with suspension and brake upgrades.
Im currently on coil overs now. Its all in a Different world.

I didnt like the stock shock feel with the swift spring on my ride. If you like the drop, just pair them up with koni yellows (what I am running and love it). If you are not happy with the drop, get coil over

With the price of Koni's you can get a decent coilovers, but koni's are koni's best suspension around.

I actually quite like the drop because it is so livable, you can actually get up driveways and over speed bumps as long as you use some sense. Looks pretty good too.

Can you give some detail about what you didn't like about the swift+stock shocks and how it improved with Konis? I wonder which has better ride quality, Swift+Koni or KW V1?

I'm just trying to do my research very carefully now because I don't want to spend a bunch more money and end up hating the ride. Ideally I need to probably find another modified G and feel the suspension myself.

Best solution is trade your G to a decently modified Z. Lol
Problem solved!!!:tup:

did you do the install yourself? konis won't make it more comfortable. it's probably your sways or the install was botched somehow. the sways transfer the force from the bump to the other side of the car, so if you hit a big bump it'll definitely be jarring.

I didn't do the install, had a shop do it. I glanced at the springs earlier looking to see if there is anything obviously wrong (like springs installed upside down). Didn't see anything.

I took a 70 mile drive today mostly highway and it was amazing how smooth and civilized it was. Great handling and confidence at speed on the mostly smooth highway roads. I think I need to get that alignment done asap since the car did tend to wander a tad more than stock. Alignment is probably off a little. The rear likes to follow the curves of the road more since there is a lot more negative camber there.

Hitting small bumps at high speed results in you really feeling the bumps and road clearly but the car very quickly regains its composure and it really doesn't feel harsh, just firm. This doesn't bother me at all. But hitting a couple of these bumps in quick succession (especially if they are a bit bigger bumps) makes the car feel like its swinging up and down and that you are losing contact with the road and it feels like crap for the passenger. I wonder what causes that. Basically there is too much body motion from those situations. I would have thought that the sway bars would decrease suspension independence but would they really cause what I'm describing? Sway bars also increase effective spring rate, but I think that only happens during turns.

Over harsh roads and bumps, the car is firmer with koni shocks over stock. With the stock shocks, I felt the car was VERY jerky when I hit a bump, didn't like the feeling at all. Your best solution is to get into different Zs with different setups and compare yourself, otherwise I could sit here for hours trying to convince you my set up rocks :)

Yeah I think suspension stuff is just too subjective, and I probably need to experience it myself.

However I do think that if the ride is too harsh for me right now, I'm thinking the konis probably won't fix it. In the long run I'll probably end up with KW V1s or stock springs but it isn't urgent. The current setup is livable. I'd hate to lose that sexy lowered look of the car too :tup:

For now I'm gonna just get my rear SPL camber arms and SPC toe bolts installed and fix the alignment. I'll also replace my dying RE050As with either S-04 pole positions or RE760 sports, both of which are quiter and smoother than the stock Bridgestones.

I have Swift on sock shocks, the ride as said earlier is actually better than with stock springs, but the rear of the car bounces too much, feels like a Cadillac when going over bumps at high speeds ... I should have done Koni shocks as I actually would want a stiffer but smooth ride. My car has very few miles, alignment is perfect, and I am running brand new tires.

I do think for someone who does not push the car or has no plans on tracking it, the combo of Swift Springs+Stock shocks would be a good one.

I am going to add Stillen Sway bars and take it from there, maybe I can get a couple of years out of these before investing in Coilovers which is the best option, things cost for a reason.

I have swifts also with stock shocks-struts and I have 66k on them (3 k on swifts) ride is very good, only thing that kills me is the 4 lane wide HUMP on the hwy I hit every morning on the way work at 80! BANG, :/

:confused: Wow, I'd say to me it almost rides better than stock. Get a second mechanic to go over everything if you are not aware of what to be looking for.

I'm on Swifts and Eibach sways (front-soft, rear-middle) currently, love the ride on the G. Only had them for less than 1k miles, the ride could still definitely use some improvement. But I do experience less body roll on turns, less bounce on bumps. Just ordered some Koni Yellows - wondering if the shocks will help with the ride. I'm also running Michelin Primacy MXV4's A/S.

Prior experience: Megan SS and V12s. Loved the handling, like rails.

Will Koni + Swift give a similar experience? Not looking to go low as I did on coils, these springs gave me the best aesthetics.

Ask Onzedge he has the koni and swift combo.
As far as from his feedback and from other members this is the best combo for your Z!

Going from a stock setup to a performance setup is not going to ride anywhere near the same. It will be stiffer. If you have some bounce, change dampers (shocks). You do not have enough damper to deal with the spring rates of the shocks. I beat G shocks are different than Z's and may not be able to handle the higher spring rate.