[pbc1548]

Hi All,

I'm considering doing some suspension mod's to improve handling and I'm interested in hearing any thoughts or recommendations you may have. Where is the best plave to begin (strut brace, sway bar, shocks, etc.) and what needs to be done to make a resonable improvement for some autocrossing and perhaps a track day or two? Any input would be greatly appreciated.

Partial Post: Please Login or Register to read the full post.

[bob blackwell]

Paul, I have made a lot of suspension changes and it really improves the handling of the 968. If your shocks and struts are worn out (test by pushing down on the car and observe if it bounces more than once before settling down) get some Koni Gas, adjustable replacements, or some Bilstein replacements. This will make a huge improvement over worn-out stock units. If your shocks and struts are OK, I recommend getting the M030 anti-sway bars. (Paragon Products or Sunset Imports have the best prices) This will make the car not lean so much in the corners and will give you lots more confidence in going faster. After that, I really like the H&R Progressive rate lowering springs for the front and adjusting the rear Torsion bars to make the car sit level after the front is lowered. Good luck and enjoy?! Bob Blackwell.

Partial Post: Please Login or Register to read the full post.

[flash]

the single most important mod i can think of is a strut tower brace - this allows other mods to be taken advantage of



the first step, upon installation of the brace, would be a good 4 wheel alignment with rear ride height set - wiht a strut tower brace, you will be able to correct the overly conservative factory settings, and improve turn in and tire wear



then, you can play around with different shocks, struts, sway bars and bushings to suit your needs - the above list is a good one

Partial Post: Please Login or Register to read the full post.

[bob blackwell]

Be careful if you install a strut brace. when I tried one it rubbed on the vanity cover (over the fuel rail and plug wires) when the engine moved under hard acceleration. The rubbing was bad enough to mar the cover as well as the strut brace. KLA refunded my money and I have not tried it again. If you can find one from Racing Dynamics which is oval instead of round, it may not rub. I still believe that if your shocks and struts are worn out (likely in a car of this age) then replacing them with better quality units is the first step. Next on my list is larger anti sway bars to control the body roll. The strut brace doesn't really come into play until you have added wider wheels with racing tires. Good luck, Bob blackwell.

Partial Post: Please Login or Register to read the full post.

[Dave]

Good input above. My premise is that everything is in good working condition (shocks/struts not worn out, all bushings in good shape, etc.), so I'll start from there:



1) Best bang for the buck in any Porsche is a quality alignment. They handle like shopping carts without one, but earn that "best handling car in the world" status with one. If you wish to do a bit of track work, it may be worthwhile to get an "in betweener" alignment set-up (not stock, not full track). Most race shops that support the PCA club racers in your area should be able to recommend and perform a good alignment on the right equipment. Costs up to $300 as I recall.



2) Swaybars - The M030 are an EASY and CHEAP upgrade and introduce a wee bit of adjustability (adjustable rear swaybar). It's a no-brainer unless you expect to move up to a more exotic set-up later, but you could resell the sways anyway!



3) Now, you stand at the precipice of the "slippery slope". You could do the Koni Yellow, mild spring rate upgrade. Or, go all the way up to full race wazoo adjustable coil-overs, etc. Lots of points in between too. With a little cruising of this forum, you'll notice a few tried-and-proven set-ups at various levels of compromise (comfort versus raw speed). Gets expensive on this slope and VERY hard to stop. Hold on to something on your way down.



Now is the time to take in a lot of info, think hard about what you'll use the car for, and pick a trajectory. I can't comment on the strut brace, haven't tried one.



Anyway, I'll sum up with:



- Make it handle like Dr. Porsche intended (all in good working order and aligned)

- Toss in the M030 sways (no loss, no brainer, easy)

- Plot a point on the slippery slope where you'd like to end up



As a point of reference, I have full-out racecar set up and even I am starting to tire of driving it on the street. Oh, for the days of a stock car and it's comforts...



But on race weekends... <img src="/forum/images/smilies/968/wink.gif" class="smilie" alt="" />

Partial Post: Please Login or Register to read the full post.

[flash]

bob - sorry to hear you have had the same problem as me with the brace



i also concur that replacing worn components as a first step - however, i would not consider that a mod, but rather a repair - i also would not consider any mods until all things had been brought up to snuff and a fair amount of time was spent in the seat - everybody knows i'm mod crazy, but i do suggest deliberate steps



now this does bring into question what the components are replaced with, which may easily make it a mod if a change of component is chosen - if you are doing the struts, it's obviously better to do the springs and go koni at the same time



on the subject of the brace, it does come into play immediately though - the effects are pretty easy to feel - the camber change that occurs due to the flex of the chassis causes odd and undesireable geometry to occur, which scrubs speed in the corners - limiting that camber change will immediately result in better cornering - you can see it as you watch cars in corners with and without a brace - the angles of the tires relative to each other are different - with the brace in place, you can take advantage of better alignment geometry - making camber changes in the alignment without a brace is sure to scrub speed - it may feel like it is turning in better, but the exit speeds will show the loss, as will the tire wear



this is even more evident as the suspension gets stiffer with mods - i had to take a run down the hill without my brace, and i couldn't get out of the car fast enough - what a mess

Partial Post: Please Login or Register to read the full post.

[bob blackwell]

Well, as the saying goes: "different strokes for different folks" I guess. We run many of our events at the same track with the same course layout in order that we may accurately compare times with different setups on our cars. My personal best time is without a strut brace (but with some very wide wheels and very sticky tires). If I thought that the strut brace would make a big improvement I would just remove the vanity cover and install the brace for track events and then remove and replace after the event. It wouldn't be difficult or take a lot of time to do. Good luck, Bob Blackwell.

Partial Post: Please Login or Register to read the full post.

[flash]

i'd try it - the bigger story though will be individual turn exit speeds - it will take a while to adapt to the increased speed and have your lap times show the improvement - you won't see it there right away



also, it may not make as big of a difference on an autocross course as it would on a road race course - there is quite a bit of testing on this on other cars, and the results would really surprise you



a lot of this will also be heavily dependent on your alignment - this is where the brace really comes into play - you can run a lot more camber and less toe with a brace than you can without



i could draw this out if i still had my drafting table, and show you how the geometry is limited without a brace, and then you could see how it affects exit speed and tracking - it's actually pretty cool to see this kind of thing - i was amazed on another car to see how this all worked out on paper - it explained why some things were happening - but that's another story for another day

Partial Post: Please Login or Register to read the full post.

[Eric_K]

I would do it like mentioned above. Makes sure you have a good baseline - maintenance up to date and a good alignment. The M030 sways are a good bang for the buck improvement. After that the decisions get harder and you need to have a good idea of what your goals with the car are and what you can live with if it is a daily driver. Simulating the factory M030 setup (adding Koni adjustable or similar shocks) is a good street/track compromise.

Partial Post: Please Login or Register to read the full post.

[Rudolf968]

As my future mod would be the suspension, I feel that the standard set-up is too hard for comfort and too soft for track. Only for street-use, I'm looking for more comfort but without tearing down the handling.

Has anyone experience with H&R ? http://www.hrsprings.com/site/index.html

H&R claims the best of both worlds, each strut has 2 springs (in serie), a small one for comfort and a stronger one for handling. The set-up is completely adjustable, the torsion bars are to be removed.

A similar suspension is used at the new VW Beattle.

To reduce body-roll in corners, I believe that the sway-bars are effective and also not expensive, thus installing one in the front seems logic, but would there be a good goal in changing the existing non-M030 in the rear to the stronger M030 version ?

Partial Post: Please Login or Register to read the full post.

[flash]

stock front rate is 160# and rear is 175#



first, that setup is for a 944S - not too sure about the fitment - there are a few differences to a 968 - the 968 is also heavier than the 944S



i would find out what rate those springs are - the small spring is really just a tender to keep the big ones in place - they will do little nothing on the handling, as they will be all but compressed once the car is on the ground



on the rear, if you delete the torsion bars, you will need to change the bushings on the end of those shocks to spherical bearings, and it does not look like they made provision for this - the rubber bushings that are in there will not support the entire load of the car - i don't know what they were thinking there, but that just won't work - spherical bearings will add road noise and harshness though, and probably not a good match for what you want



if you find the car too harsh now, i seriously doubt that any aftermarket setup will make you happy - most people generally feel the car is too soft in stock trim



to make it softer, you could change to a softer front spring, and stay away from any kind of gas shock, and stick with fluid



any increase in sway bar, will also add some stiffness to the suspension - each wheel is really moving vertically independent of the other, and each bar has a certain amount of spring rate to it, thereby contributing to the overall stiffness in all cases except where both sides of the car are going up and down completely simultaneously



i'm afraid the news is not very good - anything you do to soften it up to add comfort will reduce handling capabilities - you could try cushier seats

Partial Post: Please Login or Register to read the full post.

[Lim Yong]

Hey Flash,

How about a variable front springs with initial rate softer than stock but

firms up more than stock once loaded. <img src="/forum/images/smilies/968/dry.gif" class="smilie" alt="" />

Partial Post: Please Login or Register to read the full post.

[flash]

lol - yes - i do happen to have a set of those, and i happen to be selling them, but they lower the car a lot, and i didn't think they would work for him

Partial Post: Please Login or Register to read the full post.

[Rudolf968]

Thanks for the advices,

So H&R don't last anymore for me (big investment with ... result is avoided, thanks). I can start to change the old struts in front by adjustible fluid shocks and add a sway-bar (I really don't like body-roll in corners even when suspension will get a little more harsh). Before I'll change anything in the rear, I will collected more knowledge to make the choice that's best for me.

Partial Post: Please Login or Register to read the full post.

[Ryan]

If you look at the H&R site, the fittment is for 924S and 968 and not for a 944S even though the look-up has 944S.

Partial Post: Please Login or Register to read the full post.

[flash]

interesting - those 2 cars would need a very different setup, from spring rates, to brake duct mounts - and then there is the problem with the shock bushings that just won't last



looks like it started out like a great idea that just didn't get finished

Partial Post: Please Login or Register to read the full post.

[333pg333]

You would think that doing the carbon/glass hood and lexan rear window panel would save you a fair bit of weight? Any guess how much?

Partial Post: Please Login or Register to read the full post.

[flash]

hood about 33 if you go 4 pin - 25 if you go OEM fitment

rear window likely about 40 if you use the hatch - more if you lose the hatch and screwit right down



nothing to sneeze at, but a chunk of change to get there

Partial Post: Please Login or Register to read the full post.

[KMR968Turbo]

I have an 89 951 for which I bought and planned to install the following: full set of Racers Edge Bushings, 400 lb hypercoil springs and 31mm Powerbarz Torsion Bars. However, I recently purchased the yellow Kelly Moss 968 Turbo and since it has a pretty much stock suspension (other than being an M030) I thought I would install these components in it instead of the 951. The car rides on 265/35/18 and 325/30/18 rubber. Anyone here care to share their thoughts as to how the car will behave with the parts I have before I put them in? I'm also considering getting the Racers Edge lower control arms. Thanks.



P.S. I also bought a set of 968 M030 sway bars for the 951 but it probably won't make sense to swap them into a M030 968, right. *lol* I considered other sway bars but so far bang for the buck I'm told it's hard to beat the stock M030's. I did notice that there were a set of rear helper springs in the 968 though. Is that stock?

Partial Post: Please Login or Register to read the full post.

[Ryan]

KMR, Wow is that the car that was featured in Excellence back in 1999?

Does it have the wide-body kit? Got any pictures?



The helper springs are part of the M030 kit.

Partial Post: Please Login or Register to read the full post.