ivai

Okay. Correct me if I'm wrong please... I have a stock suspension setup with M474 option (koni yellow adjustables, but overall suspension not as good as the M030).

Currently:
25.5 mm torsion bars
150lbs front spring rates
koni yellow adjustables (all around)
22.5mm sway in front, 16mm sway in rear

Possible mostly street/decent amount of autox/a little track
leave torsion bars the same or get larger bars?
250lbs front weltmeister (from paragon)
Keep current shocks or get new ones? (I don't know if they're original or not, the car doesn't seem to bounce when i press on it)
30mm 968 M030 front say, 19mm 968 M030 rear sway

Tell me what you guys think please... I will only be doing spirited drives on the weekends most likely, maybe some (regular driving) during the week, and I (hopefully) will autox it once or twice a month... And may get to the track a couple times a year.

Serge944

Do not "upgrade" front spring rate without going higher in the rear. People have done this and try to compensate by over-dampening the rear (shocks too stiff).

In a nutshell - if your struts are tired, replace them all with bilsteins or konis. If you still have money left over, go for the 30mm m030 front bar and a weltmeister 22mm for the rear.

If you upgrade spring rate, you want to keep the basic front to rear spring rate ratio of 150/175 = .86. If something, you want it to be slightly smaller to cure the inherent understeer in these cars.

torsion mm / #
26 - 189
27 - 220
28 - 254
29 - 292
30 - 335

Anything larger than that will not be street friendly.

ivai

Okay. So heres what I'm thinking now after doing a bit more research.

250# front weltmeisters
30mm torsion bars

This combo gives me an effective front to rear spring rate ratio of .75 or so, so maybe that'll tend towards oversteer a bit.

Then just getting the 968 M030 front and rear sways.. I don't really think that it would make sense to get 22mm rear sways if i'm getting 30 mm torsion bars.

I'm also thinking I'll get new koni yellows with all this... They're gonna wear out sometime, may as well replace them while I'm doing all this other stuff.

As far as the spring plate bushings go, I'm thinking I may replace them, and am pretty sure I don't want to use weltmeister bushings (read about bad ride quality and noisy squeaking). So I'm considering either derlin bushings or polybronze bearings, price difference being around 100 bucks.

If I get all this stuff from paragon, I'm looking at somewhere between $1400 and $1750 (depending on if i get bushings or not).

Any thoughts?

Serge944

Yes, it gets very expensive, very quickly. Avoid delrin for your suspension and go with the polybronze. I've heard complaints about the Weltmeister bushings too, but I bet its mainly because people forget to lubricate the bushings causing them to sqeak and bind.

If you're spending that much money, might as well throw in some camber plates. If you dont mind the additional tire wear, camber goes a very long way.

ivai

Good point... I may as well get rennbay's geometry correction balljoint kit to get a neutral camber curve (seeing as the lowering springs will mess that up) before I consider camber plates.. Ohh the possibilities .

Macfreak007

always more and more and more money to spend...

ivai

One other thought (tell me how this seems) if I wanted to go with a muuuuch cheaper upgrade (and eventually do the rest of this in the future), I could just get front springs 250# and a rear 19mm M030 sway bar.. Would this be balanced? Perhaps a bit torwards oversteer?

tifosiman

Nope. With 250's on the front, you will need larger t-bars in the rear or coil-overs in the helper/addition mode to the stock t-bars. No other way around it. The 19mm sway will not compensate for the desparity in rates, and is not meant to perform that function anyway. You will have understeer out the ****.

Jason-85944

I have this setup.

250lb. welts
stock torsion's
koni yellow's on all corners
30mm front bar
19mm adjustable rear

If I set my rear bar to full stiff the rear of the car oversteers bad!!! I disagree with the advice to upgrade torsion bars. My .02

-J

ivai

Awesome, thanks for the input jason and tifosiman..

Jason, your torsions are 25.5 mm too then I suppose.. Just out of curiosity (a little OT), did you do the geometry correction balljoint kit from rennbay? Does lowering the car by the 1.25" increase negative camber?
https://rennlist.com/forums/showthre...11#post2521311 <-- macnewma seems to think the same as you Jason, leave the torsion bars as are, get M030 sways, and 250# welts.

Also, out of curiosity, tifosiman, what suspension are you running, or have you run, if its ever been remotely close to this?

Thanks for the help guys!!

Serge944

Yes, lowering will slightly increase camber on all cars with macpherson suspensions.

You might get by not upgrading rear spring rate, but the proper way to do it is with balanced spring rates.

Besides, are you planning to have your car really raked? The rear ride height eccentric only goes so far and it would be preferable to get into the rear torsion bar assembly and reindex.

ivai

Hmm, you make another solid point Serge as far as the ride height goes... I haven't done the rear height eccentric but was planning on it when I did all this other stuff. Would it not be able to account for the default rake plus the additional 1.25" the front would be lowered?

From the sound of it though, 30mm torsion bars would be way too stiff. I mean, I'd hate to take apart the rear end just to reindex the stock torsion bars and put them back in, so if I did reindex I'd feel compelled to get new and (maybe?) stiffer torsion bars. I think I remember seeing a post where a guy put 250# springs in front and 26mm torsion bar in rear, he said it was a pretty solid setup. I'm about to call paragon and ask their opinion...

Serge944

Id go with 29mm personally, but do call paragon - they're pretty knowledgable about the products they sell.

ivai

Alrighty, talked to Jason at paragon.. Great guy! Very knowledgeable.. Anyways, he said that he thought 250# with 27 or 28mm torsion bar would be what he'd ultimately recommend.

The stock setup tends to understeer, and he thought that 28mm torsion bar would make it more neutral. He also suggested that I try getting the front springs and front/rear M030 sways, with the rear sway at its tightest setting, and see how I like that, I can always get the torsion bars later if its too nose happy.

Now I just need to decide if I want to try and do everything at once ($$$$!!!) or do it in parts... The most I would split it up is

Upgrade 1.) front springs + front/rear sway bars
Upgrade 2.) torsion bars + spring plate bearings
Upgrade 3.) replace all four koni yellows

If I split it up like this, the order in which i upgrade may not be the order that these parts are listed (i.e. may put konis on before torsion bars)

I probably won't be doing any of this until thanksgiving break at the earliest, but I'll update this thread when I do do something! Thanks for all the help guys! I'll let you know how I like it

Jason-85944

I did not do the geometry correction kit and will not. the A arms angle up slightly, but not to the point I will be destroying ball joints. I have my car set up with -2.5 in the front and 1/8" toe out, caster at factory setting. The rear is at -1.5 1/8" toe in. I have lowered the rear eccentrics as well.

You can take this any way you like, but I strongly disagree with upgrading the torsions with 250lb. springs.

-J