how much torsion bar is too much for the Q?

[sean996]

Hi all,

Haven't been down to play at the Q in a while with my P car which is car #604 ... white 73 911S with a bunch of AM frankenstein mod's that has occasionally knocked on the door of that blue car but never banged it down .

Sooo ... been going thru analyzing why the heck this car is such a handful ... I mean it is scarey in a straight line on uneven pavement and I've been told could be a symptom of such a stiff sprung car?

I've looked at just about everything (I think???) ... so I'm pondering going to softer torsion bars. I've owned this car since '05 but only just got 'round to taking her apart ... 33mm in rear and 22mm in front. From the little research I've done seems like the only reason one would have a 33mm in the rear is for a massive wing at Willow???

Is this my problem??? Should I change the front and the rear? It feels like the steering wheel darts quite a bit and I've tried some different alignment which is why I'm questioning the stiffness of the front also? ... seems like the rear is way way too much for autocross/the Q??? I unhooked the swaybars today and went for a spin and it was still like she has a mind of her own on uneven pavement.

I'm not looking for a "comfy" street ride ... just one that's not scarey on the typical pavement that also won't slow me down at the Q ... what about adjustable shocks?? Got Bilstein greens so that seems like a step backwards??

Appreciate any input,

Sean D.

[sean996]

Browsing some other forums looks like negative camber combined with the fact that this car has not had the bump steer dialed could be contributing?

Should I play with the bump or do I just have too much torsion bar?

Thanks,

Sean

[Steve Grosekemper]

You have way too much rear torsion bar.
22/30 is what you are looking for at the Q.
Then the Bilsteins must be revalved for those torsion bars.
Rear arms need monoballs at the mounting point near the transmission.
Front end needs tie rod bump steer kit (not rack spacers)
http://www.elephantracing.com/suspensio ... psteer.htm

After all that you will need an alignment to fit your driving style.
Twitchy is fast but very hard to drive.

Hope that helps.

[sean996]

You have way too much rear torsion bar.
22/30 is what you are looking for at the Q.
Then the Bilsteins must be revalved for those torsion bars.
Rear arms need monoballs at the mounting point near the transmission.
Front end needs tie rod bump steer kit (not rack spacers)
http://www.elephantracing.com/suspensio ... psteer.htm

After all that you will need an alignment to fit your driving style.
Twitchy is fast but very hard to drive.

Hope that helps.

Thank you Steve ... yes that helps.

I made my own monball setup for the rear with all steel bearings that incorporate grease nipples vs. telfon lined that seem to be supplied in the kits and offer no provision for lubrication.

The fronts are already 22's so just downsize the rear which means only need to revalve the rears? You think this will this make the car "relaxing" to drive? Am I just a big wimp? . It's not the "harshness" ... it's the "mind of it's own" which is just scarey. Any of you guys that I know are welcome to come take her for a spin and give me your opinions/impressions ... some great roads up here in north county ... I'll let you drive a modified F car too for comparison.

Someone also mentioned the Hoosier's aren't real friendly on un-even pavement/public roads especially with a bunch of negative camber??? ... if this is the case maybe I'll start another thread about wheel sizes 'cause I have 2 sets of 16" wheels and it seemed like Hoosier was the only co. with the right size for the rears in 16".

Thanks again,

Sean

[Dan Chambers]

You have way too much rear torsion bar.
22/30 is what you are looking for at the Q.
Then the Bilsteins must be revalved for those torsion bars.
Rear arms need monoballs at the mounting point near the transmission.
Front end needs tie rod bump steer kit (not rack spacers)
http://www.elephantracing.com/suspensio ... psteer.htm

After all that you will need an alignment to fit your driving style.
Twitchy is fast but very hard to drive.

Hope that helps.

+1.

Sean:

Your car is lightler than mine and is still "sprung" heavier than mine! I'm running 21mm front and 30mm rear, stock sway bars, in a 2600Lb SC. (I do have custom-valved shocks/struts to match.) The rear of mine is a little stiff for the Q, but it's a balancing-act for a more-or-less all-'round big/little track car (plus weekly mtn drives). Overall, I'm fairly neutral with 225 100-compound Toyo RA-1/R888 tires all 'round.

As for the squirrely, twitchy, unpredictable behavior (sounds like a 911 to me ): How much camber are you running? Are you "toe'd out" in front? Do you have a smaller diameter streering wheel? Have you tried a 100 to 140 compound tire on the uneven surface streets? Bump-steer kits at the tie-rod ends definitely help.

FWIW: with my car on 200-compound street tires and a small diameter steering wheel, I still have to drive with two hands at all times. No cell phone. No coffee. No radio (well, maybe a preset CD before I take off). My car will "divert" in road seams, cracks and "unconformities". It's two hands on the wheel and both eyes forward at all times... and I'm in Stock class.

Let me know if I can help. You're welcome to PM me.