Rear Damping....need your opinion...and experience...

[935TURBO]

I just got from....US..... those perfect and nice dampers (shocks and springs)....I think I will fit them with the stock torsion bars to improve damping and to have a fine adjustment for the hight of the car....

So, who did this upgrade and did you use with or without the torsion bars and why.....???

Thanks.

[Craig 930 RS]

Helpers, nice. What pound rating?

I am a firm believer that for track use it is almost impossible to get too much rear spring rate.......heck, I've got coilover helpers in the rear with 33mm torsions. The largest torsions available. All perfect for track use.

And very little "930 squat" under acceleration to boot -

[jbrinkley]

got em, like em, with stock bars.
zero squat

[Jeff Alton]

Those look to be 150lb springs.

cheers

[A930Rocket]

If they are 150lb springs, you are going to need more spring if you are going to run them without t-bars.

My concern with helper springs or a complete conversion is that yes you can delete the squat and/or roll, but you don't want them too stiff. Some compliability or lesser of a spring will help with traction. Too stiff and the car will want to skip or bounce.

That said, I'd like to find the right combination of helper spring or coilover for the track.

Just my .02

[Craig 930 RS]

Let's get specific:

I use 24/33 torsions with 150 lb helpers in the rear over custom valved RSR coilovers.
FWIW, skipping or what have you is never a problem in any situation.

It is rough on the street, and perfect for track use. Dare I say it is actually easy to drive fast......

Looking at your (935Turbo's) hardcore 930, I'd say your car is an ideal candidate for this setup -

[A930Rocket]

For me the street is not a problem. It's a track car anyway. I want to make sure I'm no too stiff at the track that handling is affected.

I'm using 23 and 30 mm solid bars (The biggest solid bar, but would be bigger if they were hollow).

Craig, who re-valved your RSR's? Are they Bilsteins?

[Craig 930 RS]

I'd be certain that everything else can move freely; all bushings, etc - I'd assume you have poly or the Elephant setup?

Weiner down in Oregon had them revalved.
Excellent setup for track use, I could not wish for anything better.

[A930Rocket]

Thanks. I had Steve in mind for me when I go that route. I have poly every where. It all seems to work well, but there is a lot of lean and squat. I'm thinking bigger sway bars as well. I have 22 mm front and back now.

[Craig 930 RS]

You bet, glad to help.

I'd definitely obtain the raised $pindle setup up front - this will definitely make a difference as it allows the car to be lower/lowers the CG/ and gives you plenty of wheel travel.

Remind me and I'll post some pictures -

[vmb]

I hope I'm not changing the subject too much with this question:

I'm doing a coilover conversion on my 930, but this thread presented a configuration I did not think of, namely retaining my stock torsion bars, but have helper springs. I was planning on just eliminating the torsion bars and running 300/400 springs. I've searched and read the other threads on the need or lack of need for welding in reinforcements, seems inconclusive. But leaving the original T-bars in would take some of the forces off the shock mounts, right? What helper spring rate would equal the 400 in the rear? Is the only benefit of taking the Tbars out that of weight savings? I will have the shocks revalved no matter what, and I assume that revalving for 400lbs would be the same for t-bar+helper vs. spring only?

Regarding the front, I have not read anything about problems with needing reinforcements. I will be installing a strut brace. Any thoughts on the front?

Regarding intended use and the car: it's a '79 w/ a '91 C2T, GHL muffler and Andial dial a death. I don't know what turbo I have (shamefully admitted. Previous owner has it wrapped in heat shield, and I haven't looked). Will mostly see local driving (est 1-2k miles/year), 1-2 autocrosses, and 1-2 DE's per year (driven to and from the tracks).

Thanks for any thoughts!

[Craig 930 RS]

The beautiful thing is you don't *require* reinforcement with 150 lb helpers.
That said, why add 150 lb with STOCK torsions?

Get the appropriate 23-24 front, 31-33 mm rear torsions and make it a proven, balanced package.
As Steve Weiner said to me a few years ago: "There is no reason why a torsion bar equipped car cannot be made to perform in a perfectly appropriate track worthy configuration"

(I think our little forum diversions help the original poster, too ;-)

And thake that stupid heat wrap off, it's death to a turbo that does not have water cooling - advice from Kevin www.ultimatemotorwerks.com who may know more about air cooled turbos than most anyone -