Suspension upgrade

[Skorp]

Hi!

I tried searching, found no good threads. If you know of one, please link me

I have had my NA944 '82 for one month now.
Competed in the cars first autocross race, and what a good machine for this type of racing!

As you know they are very soft and forgiving when they are stock, i want to change this.
I have had Spax/Eibach combo before on a MK1 Golf, and i love to have the oppurtunity to change the stiffnes of the shocks.
I also had TA-Technics coilovers on this car which was rubbish.

I have had Yellow Konis on Lesjofors springs on a previous Volvo 240. Just soft enough to enjoy the open road, and stiff enough to enjoy Autox.

So now i have tried to push the car, i know what i want from it.

What i want to achieve:

- Less body roll: the car does not have a rear sway bar. Is this possible to get?

- Lower centre of gravity, 1-1.5"

- Neutral, or oversteer handling.

What i would like to know:

- Does it exist adjustable shocks? If not; which lowering shocks is the faverouable?

- Which springrate up front, Which size torsion bar?

- How to mount rear sway bar?

- Which size sway bars?

Thanks, I know this is something i would need to test out myself. I have somewhat limited funds, and would like do get it as close as possible to what i want.

[John_AZ]

A good beginning...

TECH FORUM General Suspension Preparation 924 944 968

J_AZ

[djnolan]

Thanks John,
Definitely worth bookmarking this link.

[fiat22turbo]

Suspension Information and Upgrades

924Board.org :: View topic - Race shock/strut options - Bilstein front, QA1 rear

[fiat22turbo]

Originally Posted by Skorp

Hi!

I tried searching, found no good threads. If you know of one, please link me

I have had my NA944 '82 for one month now.
Competed in the cars first autocross race, and what a good machine for this type of racing!

As you know they are very soft and forgiving when they are stock, i want to change this.
I have had Spax/Eibach combo before on a MK1 Golf, and i love to have the oppurtunity to change the stiffnes of the shocks.
I also had TA-Technics coilovers on this car which was rubbish.

I have had Yellow Konis on Lesjofors springs on a previous Volvo 240. Just soft enough to enjoy the open road, and stiff enough to enjoy Autox.

So now i have tried to push the car, i know what i want from it.

What i want to achieve:

- Less body roll: the car does not have a rear sway bar. Is this possible to get?

- Lower centre of gravity, 1-1.5"

- Neutral, or oversteer handling.

What i would like to know:

- Does it exist adjustable shocks? If not; which lowering shocks is the faverouable?

- Which springrate up front, Which size torsion bar?

- How to mount rear sway bar?

- Which size sway bars?

Thanks, I know this is something i would need to test out myself. I have somewhat limited funds, and would like do get it as close as possible to what i want.

Since the 944 is an evolution of the original 924 and both have rich racing histories, there is plenty of info available all over the internet. The 924 and 944 use a MK1 rabbit front suspension as the basis, so the control arms, bushings, steering, etc are very similar. I'm running polyurethane bushings for a Rabbit on my 924 and I've adapted a set of dual adjustable struts from a rabbit to my 924 as well.

On my 951 (944 turbo), it's running M030 suspension (Konis shocks/struts and bigger sway bars with 400lb front springs. It's very neutral, is lower than stock and body roll is fairly controlled. The only issue, is the rear end squat hard under acceleration, so I'm thinking of moving to 28mm rear torsion bars.



Check out the Clark's-Garage link I posted above. It lists the various factory spring rates and sway bar sizes. You can still order the factory sway bars from Porsche, you just need to cross reference them against the PET.

Here's how you get the mounts on your torsion bar carrier: 924Board.org :: View topic - How to Install a Rear Sway Bar on a 924 without one

Before you decide on parts, I'd look at trying to avoid going too large on the sway bars and focus on increasing spring rate and shock damping instead. Sway bars are a great tuning aid, but they also bind the suspension badly if they are too large and will reduce the amount of traction available as they tend to lift the inside tires.

You can get reasonably priced 28mm torsion bars for a Super Beetle for about $130, there's a link in the 924board link I posted.

Weltmeister made fully adjustable front and rear sway bars, Rennline, Lindsey Racing and Pelican carry similar items.

When you go to install the new torsion bars, read the documentation on http://spec944.org how to set the height, it will really help avoid doing it more than once.

[Skorp]

Thanks for great replies.
These answers most of my questions

I struggle to find shocks for early 944's?
Do these fit? Koni Yellow Sport Shocks Struts Set 1985 1991 Porsche 944 Front and Rear | eBay

[J1NX3D]

Hi Skorp, for an 82 you would need 86 or older. Choose your poison

Koni
Porsche 924, 924S and 944 Koni Koni Sport Front Strut Insert
Porsche 924 and 944 Koni Rear Sport Shock

Bilstein
Bilstein Heavy Duty HD strut insert for Porsche 924, 924S and 944
Porsche 924 Turbo and 944 Bilstein Heavy Duty Rear Shock.

My 86 had a 20mm front sway bar and no rear sway bar as stock. I bought a 26.8mm front sway bar, an 18mm rear sway bar (both from turbo/ S2 cars), secondhand rear drop links and new mounting hardware for the rear sway, new oem rubber bushings for them and i felt like i was driving a different car :-)

[Skorp]

Paragon got the full kit i need aswell, exept the rear mounts for sway bars. This wil also give me the oppurtunity to deside myself which springrates i choose.
I guess 350# and 31mm TB?
Think i will order this as soon as possible.

http://www.*****************.com/Koni-SPEC-1-Suspension-Package-p/944spec-1.htm

[PHillary]

you should try:

Ground Control Suspension Systems

Just search 944!

[fiat22turbo]

The sway bar mounts you buy separately anyway as they are a factory piece and will need to be welded in place on the carrier.

Though given the amount of suspension changes you're making, it may make sense to grab a spare carrier from salvage car to save yourself some time. Any 924 from 79-88 and any 944 from 84-89 can have a rear sway bar depending on the options and the carrier is the same (though the trailing arms change along the way, they are interchangeable as they mount the same on the torsion carrier)

Also look into some of the improved drop links for the rear sway bars and note the change in one of the alignment bolts on the sway bar cars to hold one end of the sway bar drop links.

[Skorp]

Thanks for the link PHillary!

Fiat: As i live in Norway, these cars are quite rare in the salvage yards.. I saw one in chrashed car that was stripped and sold in parts earlier but it was quickly "sold out" of parts!
Old Porsches do not get thrown away like a rusty jap, they stay in the garage or barn until someone take care of them!

Is this bolt you are talking about something special i need to order?

[fiat22turbo]

We were unaware that you were in Norway, it might help to add that to your profile.

Probably easiest to find one somewhere in the UK or Germany to see if any turn up, maybe even eBay.

The bolt will likely come with the sway bar kit, but I would double check when you order it.

[PHillary]

You're welcome Skorp, I can't wait until I get another 2K to spend on the car. I'm going to get the whole set. One time and that's it, ya-know?

[smudo]

I am planning to upgrade my 87 951 suspension. I use it in weekends and occasionally drive it on the track for fun. Currently it has standard suspension with Koni sport adjustable shocks that were put on by previous owner just couple of years ago. Have standard 7 & 8 PD rims with 205 & 225 street tires and front strut bar. I read several topics related to this subject and couple of links posted above and came to the conclusion, that there are several options that might be suitable for me. The favorite option at this moment is as follows:

1) Stiffer springs ( in the from 220 to max 250 lb) with 25 or 26 mm torsion bars. I would leave the original sway bars. I would change also most or all of the bushes to the polyurethane ones.

The questions/points to consider under this option would be to:
a) match the front and rear suspension stiffness to reduce the factory under-steer to neutral or close to neutral handling. As of now already know on track if you go over the limit the over-steer does not bother you much but still I want more neutral handling;
b) I would like to lower the car but not more than by 0.5 - 0.7'', but in most cases I see that you can get either standard height & rate or 1 - 1.25'' lowering springs.

2) Second option would be to remove the torsion bars and go with Koni coil-over kit.

The questions/points to consider under this option would be to:
a) it would lower the car at least by 1.25" which is lower than I want. Is my understanding correct and can you do something about it?
b) I know that the rear suspension was not designed to work without torsion bars but I have read that many still go without them without issues even on track.

3) Third option would be to install in the rear end koni 30 series coil-over kit and match it with appropriate height springs in the front (that the same set-up that you would get with Koni coil-over kit). More or less I would get the same result as with Koni coil-over kit but would loose the possibility to adjust the front height which is not an issue as I would not want to go lower then 1.25'' anyway.

Any suggestions and experience would be welcome.

[flash968]

bump those torsions up to 27 or 28 and you'll be in there. 25.5 is only 175lbs. 27 is 220 and 28 is 254

i would definitely install threaded collars up front, so that you can corner balance the car. this also gives you ride height control.

as for the rear, any coilover kit requires deletion of the torsion bars, unless you use helper springs to hold the main spring in place during wheel drop. otherwise, the preload required to hold the spring in place will raise the car, as the torsions are still supporting the weight.

[smudo]

Originally Posted by flash968

i would definitely install threaded collars up front, so that you can corner balance the car. this also gives you ride height control.

Thanks, flash, for the comments.

Did you mean something like this?

Porsche 944, 944S, 944S2, 944 Turbo and 968 Front Coil Over Kit.

I could use this kit (if it's compatible) with 225 lb rate springs and 27 mm torsion bars. That would ensure similar suspension rate in front and rear and in theory should ensure more neutral handling then standard one which has around 175 lbs in front and 126 lbs (23.5mm torsion bars) in the rear.

Do I understand correctly that his would allow me to lover the front and rear by approx 0.5'' without any other modifications?

Is there any benefit (more predictable handling, ride comfort) in deleting the rear torsion bars and going to koni coil-overs?

[flash968]

yes, that's the kind of a kit.

the stiffest spring on a 944 (other than the cup cars) was 160lbs.

generally, there is about 3/4" available in rear ride height change, without reindexing. however, if you are installing new torsion bars, you could reindex and go lower.

deleting the torsions allows for easier manipulation of ride height and spring change. it comes at a much larger expense though, as it requires a change in torsion tube bushing type to a polybronze bushing (or delrin if you are willing to grease regularly and deal with the noise), as well as spherical mounts on the shocks top and bottom. rubber and polyurethane cannot handle the impact loads of the suspension. the other issue is that there are very few hydraulic shocks out there, and the gas ones tend to make the rear twitchy by comparison. i went the coilover route on the blue car, and if i had to do it over again, i would have stayed with the torsions. i am definitely keeping them on the white car.

[kdjones2000]

I have all of those mounting bits for the rear sway bar that I took off my '78 924 before she went off to the recycler. I even have the sway bar, but not sure of the size, and it would cost a lot to ship overseas.

You would still need to weld the mounts on, or do the clamp thing on the torsion tube.

Good luck with the project...

[smudo]

Originally Posted by kdjones2000

I have all of those mounting bits for the rear sway bar that I took off my '78 924 before she went off to the recycler. I even have the sway bar, but not sure of the size, and it would cost a lot to ship overseas.

You would still need to weld the mounts on, or do the clamp thing on the torsion tube.

Good luck with the project...

Thanks for proposal. As of now I am leaning towards keeping torsion bars. In the US you have much bigger choice of non-standard upgrade parts thus most probably will have to order them from US anyway