Improved handling

ol'stupidcoupe

Registered User
I have a '90 SC that has the 1.5" eibach lowering springs w/ factory wheels & tire size. I use this as my daily driver & other than an occasional romp stop light to stop light will not be racing this or have it on any road course. I want to improve the handling on this car & I am going to start with replacing the shocks with the Illuminas. My question is, how much improvement should I expect from replacing the rear sway bar with a larger Addco one. They are available in 1 1/8", 1 1/4" & 1 3/8" and I beleive stock is about 1". It is a tough decision not being able to drive one so any info will be appreciated - what is on your car? How much improvement?
 
ol'stupidcoupe said:
I have a '90 SC that has the 1.5" eibach lowering springs w/ factory wheels & tire size. I use this as my daily driver & other than an occasional romp stop light to stop light will not be racing this or have it on any road course. I want to improve the handling on this car & I am going to start with replacing the shocks with the Illuminas. My question is, how much improvement should I expect from replacing the rear sway bar with a larger Addco one. They are available in 1 1/8", 1 1/4" & 1 3/8" and I beleive stock is about 1". It is a tough decision not being able to drive one so any info will be appreciated - what is on your car? How much improvement?

You might want to start with better springs. From my experience, Eibach's offer a decent look but lack in performance.
 
1 3/8" Sway Bars

ol'stupidcoupe said:
how much improvement should I expect from replacing the rear sway bar with a larger Addco one. They are available in 1 1/8", 1 1/4" & 1 3/8"
I have both 1 3/8" sway bars on my car. I saw a H-U-G-E improvment in the handling of my car ('89 5-spd XR-7). With the OEM rear bar, the car was absolutely violent. When I would stomp on it, the a$$ end would slide out to 45*, then violently snap back (90*) & throw the car in the opposite lane. This was due to the rear sway bar loading up, & then suddenly unloading. With the 1 3/8" rear bar, the rear of the car will step out sideways slightly, then come smoothly right back in line. No violent reactions, No lane changes, No huge steering corrections. In fact, there are no steering corrections needed at all. Just hold the steering wheel steady, & the a$$ end of the car will take care of itself! In my opinion the 1 3/8" Competition sway bars are the BEST handling mod. you can make on a Supercoupe!!!!!

NOTE: If you use the 1 3/8" FRONT bar (recommended when using the rear one), MAKE SURE that you shim the front bar away from the frame. 1/2" for sure, 3/4" would be better. If you don't the bar will be to close (about 1/8") to the crank pulley. When the suspension is at near full extension, the sway bar will hit the crank pulley. My 1 3/8" front sway bar has a nice slot ground into the top of it, where the crank pulley was rubbing on it. Dunno if it's from suspension travel, or broken motor mounts, but what ever caused it, isn't good!!!!!

68COUGAR
 
Just curious what part of the car is taking the "flexing" now that the sway bars are not. I've read horror stories of the uni body framing has to take more of the forces and cracking starts up even through the firewall......

Personally, I've seen cars (not just ours) with a complete suspension rebuild like bushings (don't use polyurethane ones on the ours for the above reason) shocks and springs.... and handling was improved huge time without swapping sway bars.

As for snaking all over the road, mine is a ninety and the springs have seen better days as has the shocks and mine has very little snaking like yours does (and YES both tires are spinning!!!!!)

I've read that the '89 and '90 style sway bars where the best of the bunch so to speak.....

Frit
 
The Illumina's are not going to last much longer than the stock ones.I changed mine to Koni adjustable shocks,best decision i have made with the suspension along with H&R Springs.
 
Re: "flexing"

fturner said:
what part of the car is taking the "flexing" now that the sway bars are not.
The sway bar IS absorbing the energy (flexing as you call it). Since it's bigger / heavier, it can absorb more energy than the OEM sway bar. More energy absorbed by the sway bar, means Less energy transferred to the body = Less Sidways motion.

68COUGAR
 
92strokedbird said:
The Illumina's are not going to last much longer than the stock ones.I changed mine to Koni adjustable shocks,best decision i have made with the suspension along with H&R Springs.

Plus the Konis cost the very same amount as the Illumina's so it only makes sence to buy the konis from the get go and never look back.

Shane
 
You didn't mention what you're running for tires, other than to mention that they are stock size. Tires make the largest difference in handling IMO. If you have cheaper stuff on there now, Pep Boys Astro Skidder GTs or whatever, spend the money for the stab. bars instead on the best tires that you can afford.

And if you are going to change shocks, as Shane mentioned Konis are the way to go on these cars. I have them, with Eibachs installed on my SC. It handles just fine. :)


cheers
Ed N.
 
The stock 90 sway bar is fine. I would say save your money. Go with Konis if you want a real improvement, the consensus is that the illuminas are floaty. They are not the same as the OEM ARC shocks. For the money your best bet is to do away with the tinker toy ARC system if you are serious about handling.
 
What about the front strut tower brace & lower engine cradle brace - much improvement? As far as the make of tires, they are G/Y Eagle HPs? I have found the Illuminas as low as $385.00 delivered but the konis $530.00 on shox. Is there another site to shop for the konis? On the shock replacement, where is the ARC control unit located & will it need to be disconnected before replacing the shocks/struts with the Illuminas? Obviously with the konis it is disconnected & left disconnected, right?
 
I just locked my shocks in firm, unplugged and removed the actuators, and then replaced the springs and shocks. Now my firm ride light is always on. Oh well. I will eventually remove the computer unit in the trunk. If I flip it to auto it clicks and the light flashes but there is no actuators to turn.
 
Back
Top