jean_noir

OK I have done the search thing And now with more information I only feel more confused. I have read about koni yellows, M030 suspension, Swaybars, springs, and shocks, torsion bars and bushings but what is suggested for a simple - mostly street set up (read better than stock but not in the $1000 range)
I have an 86 turbo that is starting to bottom out over speed bumps. My shocks are yellow but I dont see "koni" written on them. Are bushings and torsion bars really needed? Are expensive coil-overs worth it for a mostly street car? Is there a "stage I" suspension set up?

aeronautica86

if you want to increase the front spring rate, you'll need to change out the torsion bars as well, new inserts for the front struts, 220 or 250 lb springs for the front and koni sport shocks and 27 or 28mm torsion bars in the rear with stock sway bars ought to be a nice upgrade, along with new stock rubber bushings and maybe a strut brace...

jim944s2

You shouldn't be bottoming out, my guess is your shocks are shot. Coilovers are too stiff IMO for a street car, unless you are comfortable with a race-car like ride. If you want a comfortable street car, start w/ new shocks, and maybe add a 26.8 m030 spec front sway bar ('86's had little front sways). If you want flatter cornering, then consider some heavier springs for the front. The 968M030 19mm rear adjustable sway bar is a very cheap upgrade too (relatively).
You can have your stock struts modified to take the yellow koni adjustable inserts. Those on the front and the same type on the rear are nice for a comfortable street 951, and give you some adjustment range.
You can run stiffer front springs without changing the rear, my friend runs 250s on the front of his '86, and the 26.8 sway bar, with stock rear on his '86 (koni yellows all around), and he won our auto-x group last season (not a slow group either). It sounds like it should be unbalanced, but it doesn't drive like it.

ivai

jean_noir:

I did some research on this topic a few months ago.. Here were my results (sorry they're in two posts)

https://rennlist.com/forums/944-turbo-and-turbo-s-forum/233780-possible-suspension-setup-on-an-86-951-a.html
https://rennlist.com/forums/924-931-944-951-968-forum/233781-cross-posted-possible-suspension-setup-on-an-86-951-a.html

jean_noir

so basicall there are five major upgradeable suspension areas

*** Basic options *****

1) front springs (suggested 200-250 lbs)

2) 4 shocks (suggested koni or bilstein)

**** further options ****

3) front sway bar (suggested 26.8 sway bar)

4) rear sway bar (suggested stock or 19mm adjustable
or 968 M030 REAR bar)

5) strut tower brace

**** radical options ****

6) rear torsion bar (suggested stock or 26mm )
with balancing with springs as follows:

torsion mm - spring # (150/175 = .86)
_____________________
26 - 189
27 - 220
28 - 254
29 - 292
30 - 335

7) spring plate bearings

8) new a-arms

whew!!! lots of research here

just a few more questions

1) should the rear torsion bar mm match the rear sway bar mm?

2) the rear torsion bar is used to keep the rear from squatting under acceleration right?

3) the torsiom mm / spring rate chart I posted does not seem to match many peoples set up


4)IVAI what did you finally decide on and how does it ride?

5) can somebody else post their set up (spring lb,torsion/sway mm) and state how it rides?


thanks

ivai

NO. 19mm Is big for a rear sway bar on these cars, whereas 31mm is *big* for a rear torsion bar. Torsion bars basically function as the springs in the rear of the car.


Again, the rear torsion bars are pretty much the springs for the rear. To say that their purpose is to keep the rear from squatting would be a mis-statement.. Upgrading your torsion bars should reduce the amount that your car "squats" on hard acceleration though..


Just to clarify, let me quote Serge944 from https://rennlist.com/forums/showpost...13&postcount=2

He was saying the effective spring rate (in pounds) for torsion bars of a certain diameter (in mm's). Besides this, he was saying the front to rear spring rate ratio (.86, or 150/175), which would be something like 150# springs and 25mm torsion bars.


I've still got the stock suspension on mine... Haven't had the time and money yet to upgrade. Probably (hopefully) this summer.

Good thread!

jean_noir

Thanks Ivai - you info and links helped alot.

Koni adjustable = adjustable ride height correct? If I were to lower the konis by say an inch what else would need to be adjusted? would it matter what the spring size is?
or does adjustable mean the stiffness/damper resistance?

ivai

Hey, no problemo jean_noir, this stuff will be useful to me and lots of other people (hopefully) too.

"Koni adjustable" is kind of ambiguous.. Often just refers to stiffness adjustability, and doesn't necesarily imply ride-height adjustability. If you were to get a coil-over kit from paragon, for example, that'd be ride height adjustable. My car came stock with koni yellow adjustable front shocks (i can adjust the stiffness, M474 option), but I cannot adjust the ride height.

I don't think that M030 koni adjustables are ride height adjustables either.. Not 100% certain though.

ehall

Well a "stage 1" set up doesn't exist.
First, what are your goals for the suspension/car? If it is to return it to stock or a bit better, than we'll call this stage I.
To me that would be:
Replace the rear shocks with Koni sport yellows. About 250 bucks for the pair. Paragon Products http://www.paragon-products.com/prod...8040-1035s.htm
Replace the front strut inserts, on your current struts, with Koni sport strut inserts, also from Paragon for about 325. bucks. Product Code: KONI-8641-1414S http://www.paragon-products.com/prod...8641-1414s.htm
I suspect, but do not know, that you have sealed front strut inserts. If so, you will need to use Paragons instructions to modify your struts to retro fit the inserts, or you can pay Paragon to send them too you ready to go.
If you want adjustable ride height, add 30 bucks.
You are going to want new springs. If a bit better than stock is all you want than you can probably go with 200# front springs. They will run you about 160 bucks depending on the brand.
You will need to buy the mod kit if you do it yourself. It's 125 bucks.
Here's the link to the procedure.
http://www.tech-session.com/kb/index...x_v2&id=69&c=4
Here's a link to the kit.
http://www.paragon-products.com/prod...conversion.htm

That is basically a "stage I" type of a deal. You don't need to change t-bars at all. You may well have to reindex them if you aren't happy with the ride height.
As far as bushings...if this is a street car, then stock bushings are fine. You will need to check them for serviceability, but otherwise leave them alone.
Sway bars ought to be last on your mod list for a street car. They won't make anything "less bouncey" or "less soft", they will control over steer and under steer due to body roll. You won't be at the limits of your car enough, on the street, to make this a priority, until your shocks and struts/springs are taken care of, put these on your back burner.
Based on your description of bottoming out, you should be pretty satisfied with just these changes.
The next step up is full coil overs.
For that there is Koni front coil over, as above, with the ride height kit, and adjustable inserts, heavier springs, and rear Koni coil overs with t-bars, and heavier springs.
You could also use the Bilstein Firehawk set up from Lindsey Racing.
We'll call these two a stage II set up, if you want.
After that EVERYTHING is "Stage III" or just plain racing caliber.
There are Bilstein Escort Cup suspension components, like I have,with minimal adjustability, no t-bars, and an assortment of stiffer bushings etc.
Leda's with multiple custom options and tons of adjustability, Racing Koni's, motons, Ohlins etc. ALL of these are way beyond what you "NEED" for a street car.
As far as not in the 1000.00 range...enjoy taking your chances on ebay.
There is no such thing as good new suspension alternatives, as a system, for under a grand. For about 1k you can get a nice street set up.
The "stage I" above comes to 860.00 w/out shipping, and you doing your own labor, plus no core charges included. That's a hell of a good price.

A-Arms, bushings, t-bars, etc, are additional add ons that you can address slowly, as long as the current parts are serviceable.
Hopefully this will help a bit.
The very best thing you can do is call Paragon and tell them what you want to do. They are straight shooters and will take good honest care of you. You won't be disappointed.
E

phils87951

It could not be clearer, and I agree with all the advice that was put forward. Man everyone is aligned today, Maybe I should go buy loto tickets.

You can increase the front spring rate slightly. you want to stay away from increasing the rear torsion bars as the replacement procedure is very time con$uming. A little squat under accelleration is a good thing as it transfers a little more weight to the rear tires.

With the Koni's a good place to start with the ajustments is mid point in the rear as they have to be removed to be adjusted. the front is as easy as opening the hood.

If you drop the height, in the front you will have to drop the rear also, just make sure that you have enough adjustment in the rear for the ride height drop you desire, otherwise the torsion bars in the rear will have to be re-indexed and your back to the time con$uming procedure of replacing the rear torsion bars.

Koni ajustables are your best bet especially for a street car, Bilsteins are known for their high stiffness and are fixed rate dampers. IF you want to get rid of body roll, the factory 968 MO30 is your best bet, they are way less expensive and they are a lot lighter than the weltmeister bars (the front is 30mm and hollow) I use them on my track car.

Ehall, Ivai and Jim944S2 are right on the money.
Take it one step at a time, If your shocks are finished, just the Koni's alone will make a dramatic difference.

ehall

^^^^^^^^^^^^^^ I wanted Leda's, but couldn't afford them after the weakening of the dollar. DAMMIT! I do really love the bilsteins though.

phils87951

I love the Leda front canister shocks My rears are Koni double adjustables.. Spring rates are 650#f and 600# R, The torsion bars are removed..
NOT what you want for city driving.
I wish I had the funds for Leds rear canisters also.....

aeronautica86

is there any advantage to going with coil overs in the rear other than ease of adjustment? in other words, for a street/track setup, would going with front coil overs with 300 or 325 # springs, and rear koni sport shocks and 29 or 30 mm torsion bars, and say 26.8 front and either the 18 or 19mm rear sway bars be a good choice?

phils87951

As usual its a game of give and take.

For a street car I dont think its worth going to a full coil over setup. #1, its expensive and for street driving you will never use the high end units to their full potential. #2 most rear coil over setups use a modified bolt adaptor on the bottom and WHEN it brakes, you are stranded with your car sitting on the ground, with torsion bars this is next to impossible.
#3 they are usually quite harsh as they are intended for racing/high performance applications, not for comfort and comprimise.


adjustability weighs heavily in favor of the CO setup. corner balancing, alignment, ride height playing with spring rates, etc...

jean_noir

Hey Ivai, heres a good link for a variety of budgets/applications (Excellence article)

http://website.lineone.net/~dmsims/9...reparation.htm