fiream

Okay so after "searching" and reading every post and thread I could for the last three hours, my brain is going to explode because I cant figure out the right answer to my question. I need some help. I'm considering purchasing Eibach's Sportline Springs for my 83 Firebird. This car is now my primary AutoX car and I wanted to improve the already great handling of my WS6 suspension. I'm finding conflicting information on if I need fully adjustable Trailing Arms and Panhard Bar for my car if I purchase these springs. I realize that I do need an adjustable TQ Arm and Trailing Arm relocation brackets. From what I understand is that I shouldn't need anything else adjustable because i'm not going to be drag racing, i'm going to be taking corners at speed. Can anyone shed some light on this for me?

Rob...

Guest

I for one will tell you I had one of the best if not the best handing cars by statistics posted over the years on these boards ...and with that said... not one single part I put on was stock configuration. Every single part was altered in length, height and configuration. Some parts are even changed in sequence so as not to have a change, - doesn't make sense? Someday it will I hope.

Whether you think you will ever adjust something or not, buy adjustable parts and just set them to factory specs if unsure. As your suspension knowledge progresses, you will be glad you have the adjustments.

LCA's for example can be shortened for wheelbase agility, and excite roll induced understeer or oversteer with more rapid articularion change in lateral length. It can also be used to dogleg a car for circletrack, or used to equalize thrust angle of a car once in an accident.

Dean

//<86TA>\\

iTrader: (14)

listen to dean, he knows what he is talking about.

as for parts, I find it a good idea to have adjustability in parts, no matter what it is. The LCA'a will allow you to recenter the rear front to back after the car is lowered, the panhard is a must in adjustable, the torque arm needs to be adjustable, ect.

I would look into a different spring setup, the sportlines are more for looks that performance.

Norm Peterson

I'll start out by asking what class you plan on competing in, as that will make a big difference in what's class-legal.

For example, adjustable-length LCAs and relocated axle-side LCA pivots are not FS or ESP legal, but are OK at the CP level. I'm not sure what possibilities exist in the various ST classes, although the '89 Civics and the rally cars (Subies and Evos) will eat you alive there anyway.

For springs and serious autocross, forget the common street spring names and just do your shopping at the circle track supply houses. For example, you can get front rates well beyond the 700 or so that you probably have, and can get them in 50 lb/in increments should you need to tune further (which I'm betting will happen). Sportlines is a choice (?) of precisely one rate. I guess it's a choice anyway - either buy them or don't.


If you do plan on building up a CP car, you might as well choose most things to be adjustable.

If you're aiming at ESP, call Sam Strano ( www.stranoparts.com ). Multi-time national champion in FS and ESP. Or just call him anyway. Phone calls work best, and he will spend the time to talk with you without pushing any more merchandise than he feels you actually need. I will tell you up front that he's oriented toward the fewer modifications permitted in FS rather than adjustable-everything, but you can always set the adjustable-whatever to stock.


Norm

rayar

iTrader: (1)

As others have said make everything adjustable so you can make changes down the road. Not sure what class you are running and not sure how much of this is even legal for ESP so read the rule book. I also second contacting Sam Strano for recomendations especially if you are running ESP. My car runs in CP.

Definatly use circle track springs. The front springs are usually shorter so you will need weight jacks or a spacer, I went for 4 years with some homemade spacers before I finally installed weight jacks in the front. The rear can end up being a problem because most rear circle track springs are longer then stock I ended up cutting out the factory spring pocket in the body and fabricating new ones with weight jacks. It was a PITA. I am running 1000lb front and 425lb rear springs and believe it or not, I need stiffer rears.

I am using Polyurethane bushings in the front lower A-arms and they work fine at that location but, if you can do it, Rod ends would be best and also would make make the A-arms adjustable, Custom made A-arms with rod ends are on my to do list. I also found a solid bushing for stock A-arms from circle track suppliers and feel that would work well, it wouldn't be adjustable but the bigger problem is I only found it for one location so the other bushing would need to remain rubber or poly, Not sure how well that would work.

The rear lower controll arms are stock but boxed and have polyurethane in the front and modified for a rod end in the rear, I also lowered the rear pick up point 2 inches. I did have polyurethane in both locations on the rear LCA's and it worked fine on my stiffly sprung car but many people have had binding problems with polyurethane in the rear, I recomend, at a very minimum, a rod end on the axle location, both locations would be best. I also got rid of the torque arm and am using a upper 3rd link, just couldn't get any traction with the torque arm, I do believe a torque arm can be made to work great though.

Do not buy pre made LCA's or Panhard bar. Circle track suppliers have different lengths of threaded tubes and rod ends, You can make them much cheaper then buying them and you can even make them out of aluminum. You Should be able to make both LCA's and a panhard for well under $150.00. If your ultra cheap like me you can box the LCA's, cut off one end and modify it for a rod end. I might have $50 total in my LCA's and they work just as well as something you can buy.

Norm Peterson

Aluminum LCAs and other things if you poke around the site a bit.


Norm

rayar

iTrader: (1)

One thing I would like to mention is I did use the less expensive $15.00 rod ends. My car might see 50 autocross runs a year and the rod ends are checked after every event. If you do any street driving please get the more expensive rod ends.

fiream

Thanks for all the info guys. I think i'm going to set the car up for ESP, it seems to be the most moderate class and I think i'll be comfortable there. I'll also be able to grow my driving skill not worrying about breaking my daily driver, a 2007 Mazdaspeed 3 my current STU car. Anyways, I wouldnt mind a suggestion on springs, The car seems to handle very well with the stock WS6 springs. I'm almost thinking maybe I should change them and just go for some better shocks and struts. Right now I have some like $15 autozone S&S...lol I've also got a good set of wheels and tires. 94 Trans Am WS6 16x8 five stars with Toyo Proxes 4(300 AA A). What would you guys suggest doing next?

Rob...

Norm Peterson

Call Sam.

As you get more serious about ESP, think (at least) shocks/struts, and R-comps on a separate set of wider wheels that see only auto-X use. A cordless impact (2 batteries) and an aluminum floor jack make wheel changes at the lot go a lot faster. Also a more performance-oriented alignment than what most shops will give you (learning how to do your own alignments is a good thing - and unless your car has other dimensional issues it isn't as tough as the $$$$$ shop equipment makes it look).

Maybe even consider swapping between street and competition alignment settings (this can be made easy and dead-nuts repeatable, so you don't have to worry about screwing it up).

Note that grippier tires will (1) cause the car to generate more roll, and (2) tend to make it understeer a little more. IOW, don't plan on finding a combination of springs and sta-bars that will optimize the car's handling now to work as well later.


Norm