TX-SleeperC5

iTrader: (2)

First off this is on my sons 1987 Trans Am GTA:

I have done the front end rebuild, bushings, ball joints, inner/outer tie rods, sway bar bushings and shocks. I can't remember if I replaced the center link or the idler arm.

Rear: sway bar bushings and shocks.

Also installed a nice set of Eibach lowering springs.

Question: The car rides VERY rough, has sqeeks and rattles (like something is loose or broken) even with all this suspension work done. The steering had a lot of play in it so I had the steering box replaced and it still has play. The cars steering and suspension is not what it should be.

I had a IROC back in the day and that car drove and rode like it was on RAILS. the GTA is the sister car to the IROC and I just can't seem to get it to where it should be.

With all that I've done to the car (suspension wise), am I missing something ? Or is the car just so old it will never be what it was ?

If i can't get it to what it used to be, I'm considering selling the car and getting him someting else.

Any help from you guys would be GREATLY appreciated.

SlickTrackGod

Your front end slop and steering play is a result of worn Strut Mounts. The internals of the struct mounts have large rubber dounts that cause alot of deflection in turning response when you steer the car- as well as alot of up and down slop that is undampered by the front strut since the strut shaft is bolted to the strut mount.

If you pop off those black plastic caps on the factory sturt mounts (you had to when you installed the new struts) you will see the bolt on the top of the strut. Bounce the car fender and watch that bolt height position change inside the strutmount. You can also take a large screwdriver etc and pry against the side of the strut and the bolt and watch it deflect laterally inside the mount.

My advice is to buy a good aftermarket solid bearing strut mount. these are a much better design than a factory OEM replacement. You're steering response will be night and day improved. Check J&M Hot Parts for strut mounts. Great price and great product.

Squeaks and rattles come from chassis fatigue. THe only way to revive that a little is purchansing Sub Frame Connectors. THere are two types. inner connectors which are only good for drag type useage, and then outer parimeter types that connect under the rocker panels- these are a superior design since they stiffen the fore and aft flex as well as help reduce lateral twist when installed correctly and welded along their span every 6" in 1" increment welds. I will suggest Spohn performance for these SFC units, or anyone simular. Spohns units tuck very nicely and he has very good photo instructions showing the increment welds on his web page.

Dean

SlickTrackGod

Solid Bearing Strut Mounts-
http://www.hotpart.com/camaro-firebi...-black-or-red/

SFC's- My suggestion is to by "BARE" finish. You will need to weld them so any powdercoating will have to be ground off prior to this. Just by the bare ones and use black epoxy paint when fisished installing them.
http://www.spohn.net/shop/1982-1992-...-Top-Cars.html

SlickTrackGod

Actually found thes for less checking one of the board links. THese guys have copied the design of J&M and are basically the same thing for less price. I do not know the quality of bearing they are using but they are about $40 less expensive at the current time
http://www.foundersperformance.com/p...er-Plates.html

I would be suspicious of what bearing quality they are using. J&M guarantee their bearings for lifetime by original owner and use the highest quality teflon bearings. I had some prototype usints of these solid strut mounts made way back about 12-15 years ago and wore out a set of cheaper bearings pretty quickly. The high end ones I replaced them with werre not cheap in cost but lastest until I no longer had the car a few years ago

TX-SleeperC5

iTrader: (2)

WOW ! Didn't think to replace the strut mounts. Thanks for the info Dean !

As for the sub frame connectors, would body flex matter if the car ia a "hard top" as this GTA has no T-tops. Which is one thing I like about the car.

SlickTrackGod

Hard top cars are more rigid than the T-toips, and especially more rigid then convertables.

The top on the car allows for a boxed structure of the chassis making it less prone for flex. They just suffer from metal fatigue over the years like any and every chassis does.

TX-SleeperC5

iTrader: (2)

You're a wealth of info !!

So along with the strut tower mounts and the sub frame connectors, should I also replace the rear LCA's and panhard bar ?

SlickTrackGod

I just try to give honest and useful tech- best bang for the buck.

Replacing the LCA's and Panhard will certainly make the rear of the car feel more stable in performance, but is not going to help ride quality. If the car is tracking a little sketchy when power is applied and lifted (moving about in the lane in throttle modulations) then yess the car would need those replaced- otherwise, it is not needed unless you seek a car that will handle better for spirited driving. THose bushings will fles also ad the more strain on them in hard corneing or aceletating etc, the more they will deflect. Replacing them is just more money spent- it's your call whether you fell you want them or not. I would do the others first then drive it and see how it feels at freeway speed.

A side note- I generally seek the best I can find but I am an extreme chassis dynamics nut with quite a racing resume. Im fairly well know on this board and was once a NASCAR supertruck crewcheif as well. I do not believe in putting alot of money in a car that you may some day sell. DO what you have to do and that is it. Nowif its a car you will never sell? then I say go all out and have fun.

TX-SleeperC5

iTrader: (2)

This is my sons "first" car and will probably be with us fo a LONG time to come..... I just want him to have a nice well handling and driving car. When it comes time to sell, that'll be his choice and not mine.

As for the rear suspension, i was thinking the bushings in the LCA's and panhard bar may be worn due the age of the car (hence the rear suspension rattles) and some new ones would help clear that up.

Confuzed1

iTrader: (4)

Like already said -

-SFC's are going to stiffen the chassis, and get rid of a lot of those rattles.
-Replacing worn out bushings and ball joints is a must.
-The CC plates are always a good idea
-I didn't hear you mention shocks or struts?

I did simular to what you're doing to my car last year....i.e. lowering springs, JM CC plates, Bilstein struts/shocks.

I already had old style Spohn SFC's on it, UMI wonderbar, new bushings everywhere, Lakewood LCA's... and I recently installed a Founder's adjustable panhard bar and relocation bracket (to allow more exhaust room).

Of all those upgrades, the SFC's and struts/shocks made the biggest difference on my car...it handles really well.

I still have a few rattles..it's all coming from my windows, interior...typical early Thirdgen issues...

EDIT: I should add the disclaimer that I'm no "Guru"....I just got advice from others that come close to that status...lol

TX-SleeperC5

iTrader: (2)

Everything you mentioned above, ie.... "Replacing worn out bushings and ball joints", has already been done. I have also done new shocks and struts. The front suspension has been completely redone. BUT when the car hits a rough spot in the road or the highway lane makers when changing lanes it feels like it's riding on the on worn shocks / struts and springs and makes a SOLID hitting noise.... It driving me crazy t try and figure this out ! As Dean pointed out, I did forget the strut mounts. So HOPEFULLY that will make a difference.

hellz_wings

iTrader: (2)

Since you have a GTA, I don't think they came with the "wonderbar" or "steering brace" (whatever you want to call it). This is definitely a problem on these cars as the frame that the steering box is attached to gets alot of stress with the bigger GTA/IROC wheels and tires, this brace attaches the left and right sides of the front frame to reinforce it, plus the part brand new is dirt cheap. I have a TDS one with 3 mounting holes and fits fine with dual fans.

Also, check the steering for loose components like center link, idler arm, tie rods, a-arm bushings, sway bar bushings and end links, etc.. GTA had the bigger sway bars I THINK but had softer springs than the IROC. If you put on IROC springs they would be a heck of alot stiffer than what is on there now (if they are still stock GTA springs)

Subframe connectors will make a WORLD of a difference in the "handling like its on rails" feeling you are talking about. I had inner type (MAC) installed first and then 2 years later installed the outer type (SPOHN). The inners made the car feel like on rails and made it so much stiffer (this was evident after putting the car on the lift and it not cracking or bending even close to what it was before I did this) and the fact that changing lanes, going in a straight line acceleration and turning all felt so much more precise and stiff. When I installed the outers it improved upon all these things even more. Had I done outers first and THEN inners I don't know what the results would have been, but this was what my experience was with them.

I know this sounds silly but check tire pressure too, I run at 30psi. Alignment is important as well (the strut mounts dean recommended give you the ability to align it much more and better than stock, take advantage of this because it will improve handling, stability, and overall feeling of the steering and enjoyment of the car)... Tighten things up in the engine bay and the interior (maybe things are loose and bumping around in places? This happened to me so many times with battery, things inside the door, in the trunk under panels, under hood, etc.) Oh and check steering shaft for any play, I had that too, but if it doesn't turn freely with your hand then it is fine.

You said you changed bushings, is this including in the a-arms as well? That solid hitting noise might be the strut mounts that you have, OR could be something else not suspension related. Check to make sure all k-member braces and bolts are tight and in place as well. Give it a good look over.

plum92_camaro

Sounds like you've already got a lot of great info but here is my 2cents. My 92 camaro developed play in the steering. I put the front up on ramps and had the wife turn the wheel back and forth(slightly). Found my steering gearbox moving cause of a cracked frame and a bad tie rod end. I'm doing a complete overhaul on the front end this winter. Really excited to see how different it will handle with new and aftermarket parts versus the worn out stock stuff. Btw I'm adding a tds wonderbar and umi sfc.

TX-SleeperC5

iTrader: (2)

Replaced the center link on the car since I figured out it was bad. Now the steering wheel slop is gone but the rattle, clunking noise is still there. I'm guessin the strut mounts are bad.

hellz_wings

iTrader: (2)

The crack originated from the lack of the wonderbar.. You need to weld and repair that crack first and then install the wonderbar to prevent it from cracking again.

MKM

iTrader: (1)

Don't forget to check the rag joint that will cause play in the steering.

TX-SleeperC5

iTrader: (2)

It was the center link.

TX-SleeperC5

iTrader: (2)

Replaced the strut mounts with these...

http://www.foundersperformance.com/p...er-Plates.html

What a difference !! I HIGHLY recommend them. The car is at the shop getting a new front end alignment now.

1991sleeper

iTrader: (-3)

Well I have a 91 base firebird and the first thing I did to it was new shocks & SPRINGS all the way around .. New stock height springs lifted my whole car a good inch or better due to the old wire out springs .. Next I did a WS6 swaybar swap (which GTA should already have ) with new polyeurethane end links and frame bushings front and back .. Next I would replace EVeRY suspension bushing I could find (I just went with all aftermarket parts ) also I highly reccomend replacing all the old rubber brake lines goin to the calipers .. They get old and fragile and can bust leavin u with no brakes .. Panhard bar really shouldn't need to be replaced unless it has been compromised in some way .. I also reccomend new wheel bearings on a car as old as these .. Also when replacing bushings n such I reccomend polyeurethane everywhere I is much stiffer and doesn't deteriorate like rubber !

midnightfirews6

iTrader: (1)

^Poly is great for sway bar bushings, but for the a-arms the delrin Global West Del-Alums are stiffer and offer less resistance to the motion of the a-arm. In the rear end you want to prevent bind as well which can lead to handling problems by using rod ends on at least one end of the control arms and panhard bar. Poly/rod control arms and a poly/rod panhard bar is a good choice for street use. Rod/rod is even better in theory but has been reported in some cases to be noisy and will hurt ride quality a bit.

Just some things to consider if you decide to do any of those things. Poly is firmer than the factory rubber bushings, but not always necessarily the best choice.

TX-SleeperC5

iTrader: (2)

I used poly for the sway bushings and OEM for the a-arm bushings. With replacement of the strut mounts, the front suspension is now just awesome.

Now I need to get to work on the rear.... New LCA's, panhard bar and new rear brake calipers.

1991sleeper

iTrader: (-3)

Yes this is all true .. I actually have a pile Of parts setting in my garge now ready to be installed which includes 18"by8.5" C6 wheels , SFC's(outers) , adj. panhard bar (rod/rod) , and rear LCA's (poly/rod) ... I'm also about to get tubular front CA's and strut towers ... After I get done wrkin 7-12's all these will be goin on the car at the same time .. Hopefully I will be able to tell a drastic improvement .. Thought about CA relocation brackets but I'm at the factory ride height with brand new shocks & springs all the way around so I don't think it's necessary I also have a UMI TA .. So if it still wheel hops bad on launch then I will get relocation brackets I guess lol

midnightfirews6

iTrader: (1)

^Pretty easy to tell... just look under your car on level ground. If the rear control arms are level from the body to the axle, you don't need the relocation brackets. If they're angled up from the body to the axle (the axle is higher than the body), then you need them.

Or of course you can just wait and use the butt dyno and see if it squats, spins or hops on launches.

TX-SleeperC5

iTrader: (2)

NEXT ON MY LIST.....

plum92_camaro

thanx, but i got it covered. as soon as i found it i hopped on here and did a bunch of research. it goes to the body shop for the repair and SFC install in april when the iowa winter is over. A whole lot of other suspension goodies are going in too! I can't wait!

3rdgearslammer

you cant go wrong with a life time guarantee