My car rides like Poo :(

[peng155]

Hi Guy's...

I need some suggestions on changing the ride quality on the Z....

the basics are.... 71 'Z', Stock springs that the previous owner had cut to lower the car, Tokico adjustable shocks all the way around (Not sure which model, but I'm sure they aren't Illumina's). Again not positive but I believe the previous owner installed larger sway bars in the front, and rear, 15x7 wheels front, and rear... don't remember what size tires are mounted... the car is at the mechanics getting a new clutch installed. I've had the car for 20 yrs, or so... and haven't done any suspension mod's or upgrades....

What I'm looking for is to soften up the ride a bunch (I know ride quality is subjective) but when ever I go over a bump in the road... it feels like I'm riding on a brick. The car is a summer/sunday driver... no track, or x-crossing... just the leisurely sunny day Sunday drive... I've logged less them 10k miles on the car since I've owned it, and I'd like to keep the lower stance....

I don't know if the harsh ride is due to the PO cutting the springs, or if it's because the springs are worn and cut, or a combination of worn springs, and shocks.

I'm thinking about having a set of Eibach springs installed, but wasn't sure if I would need to install new shocks also... I've read that the front Eibach springs would cause the front to sit higher, and would need to be cut for the front and rear to sit level... is that still the case? Also if i need to have new shocks installed what would be a nice set-up be that would give a nice ride, but still maintain handling.

thanks for your input

[Blue]

I agree, it is probably the springs as you suspect.

Softer stock springs a bigger front swaybar, poly end links, and ball-and-socket tension/compression rod fittings would be a nice upgrade to consider.

[olzed]

I agree, it is probably the springs as you suspect.

Softer stock springs a bigger front swaybar, poly end links, and ball-and-socket tension/compression rod fittings would be a nice upgrade to consider.

Shocks can make it ride hard.
I have shortened stock springs in my 72. With stuffed shocks it was a very soft ride. New shocks made it ride considerably firmer. I now have adjustable Konis on the front on the very lowest setting, as any higher setting makes the ride too firm, and newish shocks of a brand forgotten on the rear. The ride is firm but not uncomfortable for this seventy year old

[Jeff G 78]

What bushings are in the suspension? If they are poly, I would swap them first and then see how it rides.

[Zed Head]

I've never heard of adjustable Tokico's that weren't Illuminas. Have you adjusted them down to the softest setting? That would be the first thing to do.

Do you have low profile tires? Tire sidewall is the first line of shock absorption. Old stiff tires could be a factor also.

Poly bushings probably would make for a harsher ride, especially if the small ones at the wheel side of the control arm were done. But I have poly on the inside, rubber on the outside, with 205-70-14 tires and my ride is not harsh, but firm. That's a 280Z with cut springs in the front and Tokico springs in the back, with KYB shocks.

[peng155]

Hey Jeff,

I'm not positive, but I think the bushings are stock... I'll check 2nite and see...

What bushings are in the suspension? If they are poly, I would swap them first and then see how it rides.

[peng155]

I'm leaning towards replacing the cut stock springs with a set of the progressive Eibach springs first.. if that softens up the ride, then I may consider other suspension replacement

Thanks

I agree, it is probably the springs as you suspect.

Softer stock springs a bigger front swaybar, poly end links, and ball-and-socket tension/compression rod fittings would be a nice upgrade to consider.

[peng155]

Hey Zed,

I may wrong.. and the shocks maybe illuminas.... as stupid as this may sound, I haven't messed with the adjustments on the shocks yet... it'll be the first thing I do 2nite when I get the car back.

I don't have what I would call real low profile tires, but I do know they are a bit lower, and wider then stock.. again I'll check when I get the car back...

I've never heard of adjustable Tokico's that weren't Illuminas. Have you adjusted them down to the softest setting? That would be the first thing to do.

Do you have low profile tires? Tire sidewall is the first line of shock absorption. Old stiff tires could be a factor also.

Poly bushings probably would make for a harsher ride, especially if the small ones at the wheel side of the control arm were done. But I have poly on the inside, rubber on the outside, with 205-70-14 tires and my ride is not harsh, but firm. That's a 280Z with cut springs in the front and Tokico springs in the back, with KYB shocks.

[olzed]

The first thing i would do is put the shock adjustment to the lowest setting.(If they are adjustable)

[peng155]

Hi Guy's....

Got the car back from the mechanic... And I got more info...

I stand corrected.. The shocks do appear to be Illuminas based on the adjuster I see at the top... 5 zones around the circumference of the adjuster, and it appears that all four corners are set to #1

The tires are Bridgestone RE-750, size 205-55-15... I had the tires put on about 10 years ago, but the car has been garage, undercover for a majority of that time (its been an ongoing project) but it's very possible that the sidewall rubber has gotten less pliable with time.

Something I've started to wonder is... if maybe since my cushy Honda CR-V has been my daily driver... I'm comparing an apples (Honda) to oranges (The Z) ride... and there isn't anything really wrong with the ride... I will admit being 55 yo... my definition of a comfortable ride has changed a lot from when i was a 20 to 30-somthin dip-wad.

But still would it make sense to change out the stock springs for something newer?? I'm not sure how long the stock springs should last in the 'Z'

thanks for all of th suggestions and input.. it is appreciated

[Blue]

1 is softest.

[bacarl]

Blue's right, 1 is softest, but if those Illuminas are 20+ years old, they may not have much damping to offer anymore. If that's the case the car would feel floaty over larger undulations in the road, but harsh and crashy over impacts and smaller bumps. The role of the shocks is to 1) control body motions that would otherwise go undamped and 2) absorb energy that comes crashing into the body structure.

Having Illuminas is neat because you can play with their settings and see what feels/handles the best. For starters, crank them up to 5 and see if you feel a difference. Also try the "bounce test" on setting 1 and on setting 5 and note any differences. This is simply where you push on the front end or rear end of the car a couple times to get it bouncing, then let go and note how many oscillations occur before the shocks arrest the motion. I forget the rule of thumb but you don't want the car to bounce more than 1-1.5 times; this should change depending on setting 1 vs. setting 5, if the shocks are still in working condition.

Another thing to keep in mind is that cutting the springs increases the spring rate by some amount, making them "stiffer". If you have cut stock springs and worn out shocks, the ride will likely be harsh. It's worth mentioning that springs don't really "wear out" even after long periods of time (dampers do, though). I would bet that since your coils are cut, your stock springs are "stiffer" than when new, even after all the years.

Lastly, I just put my car back on the ground the other day after a full suspension rebuild with Eibach progressive springs and Illuminas and I can attest that the rear does sit a little lower than the front, visually at least. It is noticeable to me (I'm pretty anal), but I'm not likely to hack anything up to remedy the situation. Here's a pic of how the car sits, although this angle doesn't show the ride height difference all that well. It's fairly subtle, maybe 0.5" difference in fender gap.



Play with the shock settings and let us know if you feel a change, or if the car bounces differently between the settings.

Forgot to mention, sway bars add spring rate too, although unless they're monster bars, it probably isn't significant. Bigger bars, cut springs, worn out shocks, and old tires could definitely all work together to wreck your ride.

[peng155]

Hey Brian,

Thanks for the great input... I drove the car around a bit yesterday, on city streets the car handles pretty well, the ride is firm, which I expect for the 'Z'... but when I go over say expansion joint bumps in the road... it is IMO a bit harsh...

When I got it out on the Freeway at 55+ the car does feel likes as you put it "Floaty"... minor steering wheel input to keep the car centered in the lane, translates to over correction... so it seems like I'm always correcting left/right to keep the car centered in the lane.

When I get home tonight I'll try your suggestions and make adjustments to the shock settings... take the car out and see what differences it makes...

Thanks again....

[Zed Head]

55 is a pretty low profile on your tires. You're probably going to have to choose between looks and ride quality.

[bpilati]

I agree, it is probably the springs as you suspect.

Softer stock springs a bigger front swaybar, poly end links, and ball-and-socket tension/compression rod fittings would be a nice upgrade to consider.

Ball and socket compression rods; he would feel every jolt. Don't put poly anywhere in your drive train, only in the suspension.

Eibach are progressives right? You can't cut them without messing things up I believe. Too bad stock springs don't exist anymore. We had some made many years ago and sold by Courtesy, but I think they are gone.

[Zed Head]

The Vogtland springs seem like a possibility. Not stock, but only one inch+ lower. Here's a fairly recent thread on them. You'll have to click through some links to other forums and web sites to get a good view of where they're at. Looks like they just worked some bugs out of the ordering process.

Edit - here's a more direct link http://forums.hybridz.org/topic/1176...2#entry1118171

[Blue]

Back to the title.... I would have thought a poo ride to be a soft ride?

[Pop's Z]

+1 on the ball/socket T/C rod thingums. I took mine out and replaced with new rubber bushings ( I found the plastic parts were cracked after about 10K miles FWIW). I got tired of the steering harshness over bumps etc. I actually replaced my Eibachs with my original stock springs as I thought the ride too harsh for my 69 year old butt. I also replaced the poly bushings with new rubber front and rear. Admittedly the car doesn't handle as crisply as before, but I also don't drive as aggressively as I used to, either. It's all a trade off. It still drives great and the ride is much improved. To each his own.

Cheers, Mike

[peng155]

Hey Guy's

I thought I'd post up an update on my ride quality issues....

I'm afraid to admit this but part of my problem was low air pressure in the tires..... they were about 30psi.... I filled them up to 33psi.... and that helped the ride quality quite a bit.... I also spoke to a friend and he thinks If I replace the tires that'll help some more since he thinks the tires are probably alot less plyable due to age....

Since the car will be going back into storage soon with fall on the way..... new tires can wait till next spring....

Thanks for all of the suggestions, help, and info...