Hi Guys:

The car is in for service and tomorrow they be doing the alignment I asked for after fitting the GT3 rear sway. I already told them to set the front camber for as much as they could (approx -1.4º) but what about toe? Should I leave the rear set up OEM? Whats the GT2 alignment set-up (for comparison)? Please provide your input and experiences as I'm supposed to called them in the morning (in 9h . its midnight here).
Obviuosly the intent is to make the car handle more neutral but without going zero toe and suffer the high speed instability that comes with it...

Thanks in advance

 

No one???

 

I don't have a Porsche, nor am I familiar with their particular dymanics at speed and through corners. However, in my experience, you only need a bit of toe to make a difference. I'm talking like +.1 or so degrees of toe is all you need for stability, although it is common to have a bit of toe in in front and a bit of toe OUT in the rear to aid turn-in ability without sacrificing too much straight line stability.

If you feel your car oversteers too much with toe OUT in the rear and toe IN up front, you can neutralize this by stiffening the front sway bars.

Also, you said you got a GT3 rear sway? I assume that means it is stiffer than stock. Stiffer rear suspension makes cars oversteer, so I would be careful about that. Anyway, just kind of a blathering post, but you get the idea.

 

I know that when i had my PSS9s installed I told the tech the same thing basically and he set it up with a little toe out in the front for cornering and toe in in the back for stability. I am not an expert by any strech on this but if nobody else chimes in maybe it will help.

 

front/rear toe just about covered by previous posters.

if you run 1.4 camber front and oem rear and i assume you only have GT3 sway bar in the rear (you didn't mention about front), you will way oversteer.

i run max camber, slight toe out front, slight toe in rear, -2 front and -2.5 rear on a 996C2 used for street. very neutral with mild high speed mid corner push. i had front/rear GT3 sway as well. middle hole in front, one from stiff rear.

 

atfter readind all posts and search old post here's what I'll do:

Front:
camber: -1,0º (Like Row GT2)
Toe: +3' (OEM is 5')

Rear:
Camber: 1º25 (Like Row GT2)
toe: 10' (as both TT and GT2 Row)

All of this keeping the front OEM sway bar (only 1,2 mm thinner than GT2/3) and rear Gt2/3 sway on on 2 (1 stiffest).

Opinions

 

I'd stay away from too much toe in in front. Car calls for none I think. If any, .1 toe in is better but will wear tires a bit. Rear toe in should be samll but I think car wants to toe out under acceleration anyway due to bushing flex. I's say -1 to -1.4 camber front. -.5 to -1 camber rear with no toe in rear and only a smidge toe in up front. This is good tire wear and should still drive well on street. This may be conservative for some. I am running this but I have PSS9 and my car handles great.

 

I just came from the dealer and I decided to to leave the GT2 sway bar at the 3rd hole (1 being the stiffest) and ended up with the following set up same as Row GT2:

Front axle:

toe +2' (toe in)
Camber - 1º 09' right and -1º (negligable)

Rear Axle:

toe +10'
camber -1º 25'

First impression on the road is that understeer has been dialed out and has a better turn in but the steering feels slightly "looser" at highway speeds. Keep an eye on this report as tomorrow I'm taking the car to the track and futher testing will be done.

 

As promissed...

Please let me remind you this is a RoW car being considerably lower and stiffer than US.

Rear GT2 anti-sway bar set at hole #2 (being 1 the softest and 4 the stiffest)

On the track where all road cars understeer severely, this one when tested both by me and by a Professional International Racing driver showed very mild understeer (near apex/ mid turn) with good turn in (from beginning of the turn up until apex) and slight overtsteer when provoqued (from the apex to end of turn) but overall a very "safe" car to drive even with PSM off...

On the road and using 34psi front and 39 in the rear the car's steering felt slightly darty (loose) at highway speeds (very, very slightly) kind of when you run with empty tank vs full tank and this was due to less toe in and camber increase which increases turn in sharpness but has the side effect. The car now on the road (this is very important since I spend 99% of the time on the road) feels neutral with slight power oversteering. The only thing that still bothers me is the tire pressure as I was used to increase tire pressures (BMW's) and in this car I had to lower them and quite a long way (from 44 to 39 in the rear), I wonder why is this and if tire wear increases noticeably...
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Try increasing your front pressure and see if it has any effect on the tendency to drift at speed.

 

Very intersting post kiko. I just might try these settings and see the difference. One thing though, the GT2/3 sway bar is actually smaller than the regular turbo, non adjustable, sway bar. I've been going with hole #1 and you've actually went softer for the track. Did you experiement at all with the sway bar and found that going to hole #3 from #2 makes the car more neutral. On the record, I've got the ROW package with GT2/3 sway bar, same as you do.

 

Taifong:

Increasing the front axle pressures made the steering feel even "looser" and everyone seems to be confortable with 33/38, 34/39, 33/40...

03-Turbo:

No, Everyone as Colourchange ans Zippy seems to be confortable with hole #3 (being 4 the stiffest) but I wanted to try for myself and I have't tried ant other sway bar setting yet but I'll definately try #3 as well. How much smaller is the GT2/3 anti-sway bar? It might be thinner but whats the distance of the #2 to the bend compared to the Turbo hole to the bend by this I'm trying to evaluate the lever length between OEM and #2 GT2.

 

The info about the diameter difference between the stock 996 turbo and the GT2/3 bar escapes me. I know that it's not as stiff and that's what drove me to go for the stiffest setting on the rear bar.

 

Did you try other settings? Whats your impression after fitting the GT2 sway bar on the stiffest?

 

Hm, that's odd. I guess there is no quick fix to that problem except more toe-in.