Hi,

my name is Thorsten and I am from Germany. I want you to ask if anyone has personal experience with stock 19 mm front torsion bars and 27 mm rear stock torsion bars (from the last 930 5 speed turbo)in a 89 Carrera 3,2 (with Bilstein sport shocks around).
(I dont know if the 5 speed turbo was sold in USA).
I have read in this forum and in the panorama of the pca that you often drive for example 22/28 mm, but in Germany no one I know drives harder than stock torsion bars on the street.
Even RUF recommends only other sway bars and shocks.
I think its because we have no speed limit on the German Autobahn an the cars should not be so hard at speed over 150mph.
An because of the German TüV its not allowed here to build in some other parts, which are not tested by the TÜV.
So can you tell me how this combination (19/27)would feel?
Does it have much oversteer?

Tanks for your answer and I hope you can understand my english.

Thorsten

 

Thorsten,

I used to live in Germany, so I am familiar with you question. In my opinion, the TUV is tougher than our CARB (California clean air police) since the TUV examines at the whole car.

19MM und 27MM torsion bars is a rare combination here in the USA. As you pointed out, many 3.2 Carrera owners upgrade to 22/28MM T-bars (including my '84 Carrera).

I think you will find a small improvement in ride stiffness with the 19/27MM t-bar upgrade. Hopefully, you will find someone with that combination on a 3.2 Carrera and can provide a first-hand report.

Regards, Bruce

 

Thorsten,

Are you saying you want to leave the fronts stock and only increase the rears? What concern do you want to address or problem to solve? Normally, I'd suggest you upgrade relative to the stock sizes, ie, up the front 2mm, up the rear 2mm+.

 

Thorsten,

If you were to upgrade to 22/28 like some people recommend, TüV would never know as there is nothing that can be visually inspected to determine the torsion bar size. The suspension might be stiffer, but would they be able to determine whether it was correct or not?

One "problem" you might encounter is wanting to change worn parts. You might find that the spring plate bushings might need replacing while you have the rear apart.

Viel Spass

 

Hi all together,

first I want to thank you for your answers.

BER: Yes, the German TÜV is very, very strikt and they check the whole car, even if you only build in an other steering wheel, seats, muffler- nearly everything.
Other suspension parts are a very big problem.

Bill: After 14 years I want to rebuild the whole suspension and take the chance to upgrade some parts.
The "problem" is that the car "squats" (I hope you understand what I mean) in the rear in some slow and midspeed corners. I have some pictures of an autocrossing last year which show this behavior very good.
I think I can reduce this with a bigger rear torsion bar and dont get to much oversteer (thats my question here),

Anyway I spook to 3 experts:
First an engineer who developed an coil over suspension for the 3,2 Carrera. He said the best thing to do to a torsion bar carrera (if you want to stay on torsion bars) is to build in the turbo torsion bars (27mm)and use other bushings for the spring plate. Thats all.
You can see 2 pictures of this coil over suspension on the homepage that make a friend an me: <a href="http://www.netmotor.de" target="_blank">www.netmotor.de</a> than "Startseite" "Reportagen" "Portrait" "PorscheC1 Ultra".

Second was a very good driver of the <a href="http://www.pcctrophy.de" target="_blank">www.pcctrophy.de</a> series (here in Germany) which have to drive with nearly stock porsches. He told me that they first had stiffer front and rear torsionbars in the car and than went back to 19mm stock in front, because it was to stiff. Rear would be stiffer now but he could not say the diameter.

Third I called RUF two weeks ago: They recommended stock front and rear torion bars for only street use and for serious track and street driving 20mm front and 29!! rear with sway bars 23mm front and 20 mm rear. They call it Nürburgring paket.
The torsion bars come from Porsche factory, when yet aviable.
The 23mm sway bar is RUFs own and the 20mm is again Porsche.
This all with RUFs own Bilstein shocks and a special Porsche factory spring plate with harder rubber.
You see: 3 times stock (or nearly stock) front torsion bars and stiffer rear torsion bars.
I think in Germany we use our cars in an other way than you in USA, because we have no general speed limit. We almost like soft springs and harder shocks.

Neilk: You are right: No one can see this aftermarket torsion bars when they are build in, but its illegal here!
After an accident (even without injured persons) they check the whole car and if they find anything thats not legal I have a very big problem and the insurance wont pay one cent!!!
In the worst case I have an accident caused by a broken torsion bar with injured or dead persons.
That will be my end!!
But: I will replace the spring plates of course.

Viele Grüsse

Thorsten