Fourth Gen F-body tips?
 

I'm looking for some tips and helpful advice on tweaking the suspension of my '98 Firebird to improve the handling and ride. I don't want to dump a ton of money into it at this point as I put almost $2,500 into a few years ago, so I'd prefer to stick with some of the less expensive ways to tune the suspension.

Currently the car is equipped as such-
SLP spec Eibach progressive springs
SLP spec Bilstein shocks
Eibach large diameter/hollow anti-roll bars
BMR adjustable panhard bar
Energy Suspension full chassis bushings
SLP Firehawk 17x9 wheels with 275/40/17 on all four
Powerslot slotted rotors
1LE aluminum driveshaft

Last time I had the alignment checked, I had the shop adjust front camber to almost -1 degree. I've also done some minor weight reduction, and intend to adjust the weight bias some to improve front/rear balance. The car tends to oversteer a little more now than before the upgrades, usually only when turning-in during hard braking.

I realize now that changing all of the chassis bushings out for urethane may not have been the best idea, so I'd like to start there. Which of them, if any, would be ok to leave, and which ones would be the best to change? The ride quality isn't horrible, but it does seem to jump around a lot on uneven surfaces. I rarely drive on anything but smoother pavement, my daily commute is smooth highway.

What about recommendations for the alignment settings? I love to drive winding roads whenever I can. I don't mind the steering feeling a little nervous on the highway, I'd rather have the responsiveness than a vague feeling on center. I'd also like to get into Autocross if I could so settings that would be a happy medium, if not slightly more aimed at track days, would be preferrable.

Also, my limited-slip is less on the limited side these days. I don't want to spend a fortune on a new unit, as it is just the weak 10-bolt. What would be some decent limited slip units to replace mine with that will accommodate the same 3.42 gearing the car came with.

I appreciate input on this project, as I hope to start working on it as the weather begins to get warm again. I won't need to rely on the car for daily use once spring hits (have a Ducati for the nicer weather).

Anyone have any suggestions?

Poly are better than stock but see if you could swing a delrin set.

Go with a tru-trac carrier swap, maybe 3:73's and axles while you are in there.

C5 front brake swap and ebc red pads.

Energy suspension trans and torque are mounts.

Get a tunable rear away bar.

Alignment setting you will have to play with. You might want to look into higher adjustment caster/camber plates.

I would think the delrin bushings would cause more bind and less control, right? They're much stiffer, so I don't think they'd be a good choice in the rear control arms. I'm not opposed to a softer bushing with a little more flex, like neoprene, but I don't want to loosen up the suspension too much. Every bushing or mount that could be swapped for urethane was replaced. So I'd like to consider changing out some of those as a starting point, and then work from there. I still want a responsive feel in the car with a little more compliance in the ride, but I'm not looking to make this ride like some high-end luxury sedan. I just want to get some of the jarring and twitchy feeling worked out.

I'd rather not swap the gears in the rearend. With the car being an A4, I feel like the 3.73 would be just a tad lower than what I would like. I've driven some with lower gears in them, and wasn't that impressed. But I definitely will look into the Trutrac.

I've considered the C5 front brake upgrade before, and I may bite the bullet next year when I need to buy new rotors. I'll probably also go to some braided lines when I do. I feel that the front brake upgrade would help lessen the rearend's tendency to step out under braking. It has come around on me a couple of times when braking too hard with just a slight input from the steering. It rarely wants to oversteer when staying neutral on the throttle or accelerating out of a turn. So my concern with the braking oversteer lies more with the brake biasing or possibly even some stiction in the rear suspension. That, combined with the overall stiffer feeling of the rear when there's no added weight over the rear axle, make me feel like perhaps the urethane control arm bushings were the wrong choice. And, I've heard some people were happier with neoprene bushings instead of urethane.

Unfortunately, with no access to the right type of resources to check or test changes like these, it's hard to know what's best. I pulled the trigger on the full-chassis urethane route without having any then of getting advice on the best route to go. I just knew that higher durometer bushings than what came on the car would help in the handling department.