99'CajunFirehawk157

iTrader: (57)

We purchased our car for one thing: pleasure rides/trips on the weekends, car shows, cruises, etc. No racing of any kind, just top down cruising. Our car has bone stock trans am suspension, original deCarbon shocks, slp added bushings (?) and no mods what so ever on the suspension. W/ 55k miles the ride quality at 40 mph on a scale of 1-10 is about a 5-6 at most , at 75-80 she rides smooth has silk. My quest and number one dislike about this car is the low speed ride quality. :faint: I also have issues with corners at low speed such has going L or R to a side street, the car seems to side step and sways a lot it seems too.
What can be done to correct these issues?
Remember, I am looking to achieve the best overall ride quality, period.

PLMK

subtlez28

iTrader: (15)

That side step issue will be nearly illiminated w good shocks. Its been said a million times but stock shocks suck! I highly recommend KONI SAs. They are not just for racing, they will improve ride. The adjustability allows you to set them soft. I was hesitant to spend the $, and ride quality was a priority for me also. But I was amazed! The ride, especially in the rear was night and day. And when I swapped them in my car only had 19k on it, and the stock shocks were functioning well (for decarbons).

RevGTO

iTrader: (12)

If ride is your only concern, I'd recommend getting Bilstein HD's and keeping the stock springs. Half the price of the Koni's and will improve ride considerably, as well as curing your skipping problem. Get some tires with soft sidewalls - avoid any of the KD series BF Goodrich tires. Keep your tires pressure at 30lbs. or under. DO NOT put SFC's on your car. If you have any polyurethane bushings on the car, replace them with factory rubber. But as Subltle says, shocks are the biggest part of the equation.

coolformula

iTrader: (21)

Get some Koni SA's.
A poly panhard bar (Don't want rod ends nosie/wear no racing application here) this helps side step.

are you running stock 16 inch wheels? If not 16 wheels might give you more cusion and ride quality with some good tires!

I would put a 35mm front bar on it to help sway and this shouldnt hurt ride quailty either and save a couple of pounds. I like the sam strano 35mm hollow bar.

99'CajunFirehawk157

iTrader: (57)

I have stock 17x9 SLP firehawk wheels...lo profile firehawk tires too, 40 or 45 series I think.

jmilz28

iTrader: (13)

Shocks are definitely your priority. Do this first, period. Konis are the best shock for real world money. Best bang for the buck on stock shocks is the Bilstein HDs. Get either from Sam Strano. www.stranoparts.com
Call him on the phone and get his advice.
I just did Bilsteins and it was night/day, like a different car.

Shocks shocks shocks shocks!!!

shudog

iTrader: (3)

I added Koni SA's up front and Bilstein HD's out back with stock springs. Ride was improved. Added aftermarket rear control arms and ride turned to crap. Constant rattle at low speed over every little crack in the pavement. Added subframe connectors and it actually got worse yet. So stiff it's actually jarring in some aspects. Its so bad it's downright embarrassing when I have someone in the car that's never ridden in it before. I have to completely avoid certain roads and others I just punch it to distract their focus from the rattle trap suspension to the roaring engine and pure acceleration....

DrkPhynx

I'm in a similar situation CajunFirehawk. I really suspect the majority of people here are racers of one type or another, and that colors their advice. From the perspective of a race car, my car rides like a DREAM, *however*.... that isn't my perspective.

I differ in that I'm chasing the optimum balance of, and maximizing, both, ride comfort/quality, and handling. (I realize that one will ultimately require the other to sacrifice to go past a certain point, but I just want both taken to their limits and nicely balanced, it's neither a Maybach, nor a Corvette afterall. )

Anyway, I just wanted to say, with everyone recommending Konis... they WILL firm up your ride. Over shallow rises or dips (especially at low speeds), you'll love it. But over recessed manhole covers, lips in the pavement, small potholes, etc, you WILL feel a firmer ride that will send shockwaves into the cabin and rattle things.

Tires and pressure will help, but I went to a softer sidewall tire and have run pressures as low as 30F/28R and still felt it. Worse, I can also feel the sidewall flex on turn in and quick same-lane avoidance. (and to force it, snap the wheel side to side a little bit, and there will be a delayed yaw oscilation on the sidewalls - I've gone up to 34F/32R to try to cure that, and the ride comfort/quality feels no different than it did at 30/28)

The tires I got were BFG g-Force. Tirerack rated them as higher comfort and grip than the stock GY Eagles. Going softer still would start to get scary I think.

If you're not taking hard turns, keep your stock PHB, LCAs, etc, don't put SFCs on it, and just upgrade to Bilstein shocks, revalved by Strano if possible. And check your tire pressure.

It might not hurt to try some lightweight brake rotors and rims too (drilled and slotted rotors can be lighter - they will be more prone to warping and failing under abuse, but if you're not racing the car or even pushing it hard.... you could probably get away with it, those and ligher rims will help reduce unsprung weight, which should help the wheels get up and over bumps more easliy).

I don't like the shock that feels like I just hit a damn curb when I roll over uneven pavement (a road surface level change, for instance), at more than 20mph. But... I love everything else about the car and ride. I just have to cure the damnable clunking in the rear and I'll be happy (and just live with the highspeed shock from rough pavement/bumps at any speed over parkinglot speeds).



Just for the record - I have SLP SFC's welded in, a UMI rod ended PHB, and Koni's all around. (and did the front Koni lower perch/rear heater hose mod)

RevGTO

iTrader: (12)

I don't think your Koni's are responsible for the impact harshness you're describing. It's the damn SFC's. I had stock shocks on mine when my SFC's were welded in and the increase in impact harshness was dramatic. That forced me to get better shocks. The Bilsteins alleviated a lot, but not all of it. I remember feeling that after I got SFC's ... I had an older passenger and every expansion joint was a shock to the cabin - it felt ridiculous. SFC's = my least favorite mod, although they seem to have gotten better with time or I've gotten used to them.

DuronClocker

iTrader: (25)

For a best combination of handling/ride quality, I'm going to recommend Sam's setup. Really, the Konis felt better than my stock worn out shocks, but I really was not incredibly happy with the ride quality this year (after SFC install! last year was better before SFCs, but I wasn't focusing on ride quality at the time). When I installed Sam's springs instead of my stock springs, the ride quality definitely went way up, and the handling did as well. For some reason, I didn't think the Konis and stock springs worked well together. Maybe the Konis need a higher spring rate to work optimally?

My car's ride would probably be perfect if I didn't have my SFCs, chassis-mounted torque arm, and my crappy LCAs. I've debated taking the SFCs off, but I don't want to be twisting this chassis up at all launching at the track.

RevGTO

iTrader: (12)

Same here. A nine inch crease in my RR quarter panel was what motivated me to put them on in the first place.

DrkPhynx

It's very possible that it is the SFCs that are largely responsible for the *level* of impact harshness, but... the chassis should not be a 5th spring. And I'm not saying it is (4th Gens are built like tanks as it is, and there's one that was drag raced and road raced for about 200,000 miles and is still fine - no SFCs or cage), but, having a stiff chassis can't be the cause or reason for this. Other cars are as stiff or stiffer and don't suffer from it.

I wonder if the car is acting like a drum of sorts and the sounds are being magnified.

It's really the sound that is killing me. I personally don't mind the feel in the *** as that is negligible, it's the crashing and rattling that it stems from the crashing that is killing me.

My suspicion (and not being a suspension tuning expert, it is only a suspicion) is that the high speed bound/bump (compression) damping of the konis is the issue. When you compress them slowly, they give and it's soft and it's great, like I said above, small gradual rises or dips are just fine. But force it to move quickly, and it resists heavily, causing the tire to crash into the bump, rather than rise over it.

I understand that these cars have a lot of unsprung weight. So it might be something we just have to live with.

If my drum/chassis theory is correct, then lots of sound deadning would solve all the problems. I just have to get the cash to do it. (and I am reluctant because it's heavy enough as it is)

RevGTO

iTrader: (12)

Right. After I got SFC's, and the "crashing" got so much worse, I was motivated to chase down and eliminate every interior rattle I could find. I noticed that the impact harshness didn't bother me as much with the t-tops off. So, like you say, it was more the noise of it than the actual sensation. Eliminating interior rattles really helped.

01Z0H6

iTrader: (63)

May i throw in my .02..?

How much $$$ you willing to invest for an fbod to ride like a luxury sedan.?

I'll tell you what i did, and right up front, my car does not drive like a sedan. However, it is very smooth throughout the RPM range.. Drives/Rides nice and solid!

I am running the Bilstein HD's, Hypercoil springs,LGM sway bars ( front/rear), SFC's, LGM Adj PHR, LGM adj LCA's, LGM Relo brackets,

Good luck

ErikElvis

iTrader: (1)

I bought my car with 25,000 miles on it. Ride was nice. I then swapped to hotchkis springs and Koni SA's up front. Been slackin on gettin the rears. But anyway I cant complain about the ride quality at all. It feels solid but not rough. But everyone has their tastes and thresholds. I have my SA's a tad softer up front then most reccomend.

RedZ99

iTrader: (1)

I'm kinda like you, cajun. I wanted a good driving car, not a drag strip dominator. I've added the Koni SA 4/4 setup, with the Strano swaybars front and back. I removed the rear spring rubber, installed some McMaster-Carr 5133K14 silicon hose (2' left over from another project) on the top of the rear springs (used soapy water as a lube inside the hose-worked great). I used the lower spring purch on the front shocks. Bought some new brake rotors (plain) with Satisfied GS6 carbon ceramic pads all around. Added Goodyear GS/D3 tires in the stock size (16" on a Z28; sticky STICKY tires!) to all four corners.
End result: This damn thing really sticks to the road. No tail-swaps. Leaves um hangin' back at the turns and lights in town. Fun to drive on rural roads. Drives ok down the highway. And it really made a difference in all the little squeaks and pops in the body/suspension. Much quieter. The GS6 brakes pads are ok, and the wheels stay cleaner, longer, and the new rotors brake so smoothly. That was a year ago, and i still have some improvements to make, but it was a heck of a start! Calling Sam Strano isn't a bad idea; he may recommend his custom Bilsteins, which are cheaper than the Koni stocks. MY Z drives much better to me, and my girlfriend, than her '03 Buick LeSabre. Just don't confuse a NeedleNose or 'Bird with a Caddy.

z28bryan

iTrader: (7)

Ride quality is such a subjective thing. How do you define ride quality? To me, ride quality is having a comfortable daily driver.

gun5l1ng3r

I have the EXACT same problems with my Koni's and I cam to the same conclusions as you. The compression setting seems a little too high (in the rear at least) and combined with a 17" wheel and 40 series tire and lots of unsprung mass, and you have the wonderful Fbody ride...

I don't mind it most of the time...When it gets warm outside though, I get irritated and every little annoyance in my car seems worse...

Greggy

lower air pressures.

When it gets hot out the air pressure in the tires can rise drastically. I found that 32psi front and 29psi rear @ 70* tire temp. is good for wear, handling and ride. I hated my ride with just one or two psi more when it got hot out. Your setup might be different though.

subtlez28

iTrader: (15)

I thaught my ride was kinda harsh (especially over expansion joints and similar) w the stock springs(lower perch/hose mod), konis and 17s. I dropped pressure some in the tires-that helped a little. Then I added higher rate springs(stranos). You feel the road alot more-especially dips and rises- but the impacts of things like expansion joints is greatly lessened. I like the ride much better now, but it is subjective...I'm assuming some people would find the reactions over dips/rises unsettling. It makes for a much more sports car feel, less Caddy like float.

Is that clear as mud? Kinda hard to explain in text...