ok, so i fitted eibach springs on my 87 a few years ago, i also removed the stock rubber isolators and replaced them with some thin rubber to get it sitting down a bit more. The car crashes over bumps in the road and rattles around quite a bit on shoddy roads.

now, ive also got an 84 project car which ive fitted new shocks too but its still on stock springs, i drove it up and down the road today as it hadnt moved for a while and it rides pretty smooth, baring in mind on this same road ive driven my other car and it rattles over the bumps.

do the eibach springs make the car a lot stiffer but rattle more or is this because the stock rubber isolators are gone ? maybe theres not enough padding between the spring and the chassis now so its rattling a lot more ?

 

The Eibachs being stiffer will ride harsher and could induce more vibrations and crashing noises. There are too many variables to make a real comparison here though as to the Eibachs being the cause of your issue. The Eibachs don't make the car stiffer (that would be the act of subframe connectors, strut tower brace, beefed up suspension bars and brackets) they will make the car ride harsher over bumps.

 

So basically eibachs are **** for regular road use then. Pretty much what I suspected lol

it' making me not enjoy driving the car to be honest. Once I get on a smooth road it' fine but going round town and our crappy roads it's pretty harsh. Sounds like something is totally loose at the rear of the car sometimes the way it rattles around.

so I might have to pull the eibach springs then. What' the best stock replacement spring for comfort. MOOG ?

 

Yeah, MOOG is a great stock spec spring for road use. There are a few different spring ratings a camaro came with, I don't recall the part numbers but if you search you can easily find them. I have been using a set of MOOG with a coil cut for Autocross for the last few years. I'm no pro driver but I've been pleased with them.

 

Sounds good man. I just want a nice smooth ride and thats it. I went with the eibachs as my car had huge wheel arch gaps and looked terrible. That was with the ws6 springs with it being a GTA and I went down to 15" wheels.

it was a bit rattly with those springs too but I don' think it was as bad as it is now

 

Im also wondering if I take the eibach springs out and put in some thicker rubber to simulate the isolators would it absorb these rattles somewhat? Maybe the rubber stuff I used was too thin so that's what the extra rattling is about ??

it was pretty thin rubbery foam stuff I stuck to the top of the springs before installing them

 

Just to clarify, is it the front, rear, or everywhere that you're hearing the rattling? After reading through everything I'm starting to suspect that there's *something* rattling and the stiffer ride is just amplifying it (you mentioned you heard the rattling with the stock springs too).

 

Seems to crash at all 4 corners. The rear seems louder though but I don't know if that's just because the rear of the car is all open so you can hear it more inside the car.

 

What are you running for shocks and struts? If you're running some Gaybriels or Monroes, or KYBs, you probably don't have enough shock/strut to control the abuse of the springs.

Did you or someone else, remove all the sound deadening? How's the foam rubber between the tank straps and tank/body and tank? Spare tire snugged tight in it's cubby? Rubber isolator between the lug wrench and body? Rubber dong-ring on the extension? Stock suspension bits in back? Poly bushings? How secure are the interior panels? Are all the plastic push-in keepers, and threaded inserts, etc tight? Or hanging on by just a thread? How's the NVH foam between the door skins and impact bar? Roof skin and structure? Running a nice thick factory headliner or one of those thin ABS monstrosities?

I'm just throwing these things out there, because there can be a million reasons for a harsh noisy ride. Probably the #1 cause on our car is running bargain bin "one size fits none" shocks and struts. They might be great on the family truckster minivan, but they're going to have problems with WS6 springs, much less lowering springs. Foams and rubber, and NVH adhesives can dry out and decay with age. When the rubber gets hard, or cracks away, or dries up and blows away in the wind, it won't be able to soften the impacts of a rough road.

Of course it's also worth mentioning that these cars, especially the factory 16" wheel/245/50 versions all ride a little rough.

 

I fitter Gabriel struts up front a few years ago. Kyb gas adjust shocks the same time I done the springs. No idea what the tank straps etc are like I've never had to pull the tank. I took the spare wheel etc out of the car to rule that out. Couple of clips missing on the interior plastics but not enough to make clattering noises like that.

it' got hotchkis tubular panhard bar and UMI tubular control arms at the back.

 

Sounds odd to me my old formula I had was a ruff ride stock I put in a pro kit and it rode very smooth and handled like poo with them but also lowering springs will make short work of cheap shocks and struts think mine were shot in a few months.

 

Hmmm. Not sure what to do then.

 

Get some Koni or Bilsteins up front. For starters.

 

I agree. Buddy of mine lowered his Z28 with the prokit and kyb's. Was vary disappointed in how rough the ride felt and just recently upgraded to koni's and could not be happier. Good set of shocks and struts DO make a world of difference

 

More money..... not sure exactly how much they would be front and back but sounds expensive. I think I would rather just go back to stock springs like Moog or something

 

Oh it's only about $700-ish US to do all four corners. The catch is that anything stiffer than a V6 or FE1 suspension is going to require a quality shock absorber. You could start by putting the rubber isolators back in, but really the expense of quality absorbers is just a necessary evil for these cars.

 

When I replaced my OEM spring with pro kits. The ride quality was actually better.

 

crazy. Did you keep the stock rubber isolators ?

 

Yes I did. The stock springs at the time I removed them had about 70,000 miles on them.

 

I think I will get some new isolators then and try that. I know I didn't keep the old ones. Damn.

I've had a look on rock auto but they only seem to have thin type things ? The standard ones were big chunky things

 

I just put a 89 GTA back on the road. I had to replace the fuel tank, pickup assembly, and fuel pump so I figured I may as well fix a dragging front brake and upgrade the suspension while I had it apart.

I installed the Eibach sportline springs front and rear, the rear shocks were in good shape but the front struts were suspect so I replaced them with KYB damping adjustable units. I put the factory rubber isolators on the tops of the Eibach springs. New sway bar end links are on as well as well a one piece adjustable tubular adjustable panhard bar.

It lowers the car about an inch or a tad more and looks bad ***. The car rides a bit more stiff/harsh than factory. However it also corners DEAD flat. It's like it's on rails. I didn't note any more rattling or noise than any other Gen 3 GTA I've been in. I handles similar to the 85 C4 Corvette I used to have with the Z51 suspension. What is all the more impressive about this is, the Z51 Corvette suspension is a Dana independent rear end, and forged aluminum indy car style front suspension. It was the first American car to ever hit 1G on the skidpad test. I think the GTA is heavier and has less tire footprint so not sure it'll do 1G but it will be pretty close.

If you are concerned about comfort, stick with the factory springs. I mean, the factory Firebird suspension was pretty good for all around driving and the WS6 suspension is already REALLY great handling. If you are willing to sacrifice a bit on comfort for a lower stance and even better handling in corners, the Eibachs and quality shocks/struts will do it for you. Just remember to put the factory rubber isolators on the top of the new springs when you install them, and also, clock the front springs correctly with one of the two inbourd holes in the lower a-arm covered and the other open.