New Bilsteins!

[KevinS]

Just got back from my house in Bremerton, Washington where I keep my car stored. After researching here on the website I went with a new Bilstein HD's all around. Car rides and handles great. Being a 1971 911 T it does not have any sway bars and still rolls, especially in the long sweeping high speed corners. Any input on what to do? Stifffer torsion bars? Sway bars? The car is only used fro touring so I'd like to keep the ride on the soft side.

[Jeff Alton]

A mild torison bar upgrade and a set of adjustable sway bars will make it handle like a different car. The ride would be firm but not bone jarring at all.

Jeff

[masraum]

I vote that you go with Sways first.

[KevinS]

So what will effect the cars ride the most? The addition of sways bars or stiffer torsion bars? Has anyone installed sway bars on a car with out factory ones? Weltmiester the way to go? anything specific to worry about or look for. Thanks for the input.

[pwd72s]

An earlier post here suggested some aren't too thrilled with weltmeister fittings. You might do a search. I'd suggest looking a factory bars, tuning the torsion bar size to match the sway bars. In other words, as you go up in size with T bars, perhaps a bit of the same with sways. My car is pretty stiff...22's (maybe 23? I forget...the bars installed back in '76) and 28's on the torsion bars, 19mm on the sways. Using factory mounts. Now that I'm only street use, I sometimes wish I'd gone not quite so stiff...but I don't wish that enough to change back, since I like flat cornering.

[911-32]

I used to have a 72 with no sways. I put 19mm bars front and rear, with adjustability on the rear. They were similar to Weltmeisters in quality but made up by my mechanic for somewhat less cash. Used with Koni Red shocks and standard tbars they provided a very nice ride and a decent amount of roll resistance campared to no sways at all. My car won a couple of club level autocrosses so it certainly handled ok.

Remember that the 72 cars that had sways had them in 13/15mm diameters so even 19mm is a lot stiffer than original equipment. Given the advances in tyre technology, 19mm seemed about right to me for a mainly road driven car. Going much bigger than 19mm would IMHO start to effect ride if used with std tbars. My experience with my current 89 car is that big tbars have a much greater effect on ride quality than "mild" sway upgrades.

HTH
Richard

[RickM]

Originally posted by 911-32
My experience with my current 89 car is that big tbars have a much greater effect on ride quality than "mild" sway upgrades.

HTH
Richard

Richard,

What size T bar did you go to on the 89? Is your ride quality comment positive or negative?

Thanks

[masraum]

Torsion bars will make the ride stiffer (which will make it roll less), sway bars make the car not want to roll in turns, but shouldn't affect ride quality much. You should be able to go with some reasonably sized roll bars which should transform the cornering of the car without making the ride more harsh.

[Oldporsche]

When I bought my '70 911E it had the hydropneumatic front struts and no sway bars at all.

I converted it a step at a time. First the struts, and "T" torsion bars, next front sway bar and later rear sway bar.

The handling was improved do to more predicitability. And the ride was unaffected. Each step was an improvement. Before installing the rear bar, I was known to carry the car on three wheels in an autox. Believe me, I had good pictures and lousey times.

I used a through the body, (stock) front bar. Useing adjustable drop links up front turned out to be a good choice for me.

I would go with sway bars and stay away from larger torsion bars until I got the new handling down.

Good luck,
David Duffield

[randywebb]

"sway bars make the car not want to roll in turns, but shouldn't affect ride quality much"

Yes. You want to think about what they actually do. They tie together the two sides of the suspension. The suspension is less of an independant suspension. They only affect ride quality when both wheels hit a bump at the same time. If only one wheel hits a bump, the sway bar will not add anything much to the spring rate. Tho there will be some transfer of twist to the other wheel.

Make sense?

[DByers]

Kevin, I have the same car as you and went through alot of this just recently. Here is what I ended up with,

21F torsion bars
26R torsion bars
22mm front adjustable threw the body sway bar
21mm rear sway bar (getting installed tomorrow)
new HD on all for corners
new bushing all around
15X7 fuchs on all 4 corners on 205/60
align and CB
turbo tie rods

She handles fantastic and thats without the rear sway (front as soft as possible). Street ride feels better then before (33 year old parts dont ride as well).
Will have her on the track by years end for a true test of how all these upgrades have helped.
I am hoping her nick name may be a thing of the past after all this. She used to lean like a sail boat in a gail when cornering.
Very soft suspension and the 14" fuchs didnt help. So she got hit with "Stay Puff" and it has kinda of stuck.

[DByers]

A recent pic

[KevinS]

Dan,

I know that I’m biased in that we have identical cars, the only difference I can see is my interior is tan. But I have to say your car looks great. RS flares in the back? I like the Porsche letters on the side. You say you have 205/60’s all the war around, your rears look bigger than your fronts? What kind of front adjustable sway bar did you go with? Why not put another adjustable on back? Hope you don’t mind if I copy your car. Could you send email me a photo so I can just give it to the restoration shop and tell them to make it look like this.

Kevin

[DByers]

Kevin, Thanks for the compliments! I have had this T for 18+ years now and she never ceases to amaze me.
The front sway is a Weltmiester. No adjustable on the rear. I was on a budget and had to be carefull not to go overboard. Once the suspension is set I dont see myself adjusting the sways. Kinda of lock and load. She is still a narrow body (no flares) and I plan on keeping her that way. The interior is basic low key RS and the seats are now Classic II with 4pt harness and harness bar.
The rear looks bigger probably from the angle of the picture. As soon as the need for tires arises I will go to 225/50 rear and 205/50 front. The 15X7 really add a certain tone to her. Rocker trim is going back on in a few weeks more then likely.
Here is a before pic with the 14's

and one of her at the track pre suspension mods


If you want some more pics of her just let me know.

[KevinS]

Dan,

Yes, I like to see some pictures of the interior if you have them. I'd like to go with the RS carpet as well and delete the rear seats. Are you happy wiht the results? My car came from the factory with 15x6 fuchs and due to the expense of replacing them I'd like to keep them. Did you have to add spacers to fit the 7" rims? I was wondering if 225's would fit in the rear. I'm thinking of going with 205's in the front and 215's in the rear, probably 50 or 60 series. Thanks for the pictures and info.

Kevin

[911-32]

Originally posted by randywebb
You want to think about what they actually do. They tie together the two sides of the suspension. The suspension is less of an independant suspension. They only affect ride quality when both wheels hit a bump at the same time. If only one wheel hits a bump, the sway bar will not add anything much to the spring rate. Tho there will be some transfer of twist to the other wheel.

Make sense? [/B]

Somebody beat with a stupid stick if I am wrong, but I think this is backwards. Because a sway bar couples the wheels together, it adds zero to effective spring rate if both wheels hit the same bump or hollow. Its when only one wheel hits a bump or drops into a hollow or hole that the sway bar twists and adds effective spring rate.

To answer the other question, I have 22/29mm tbars on my car and the ride is much stiffer. I like it (for reasons other than ride quality), but objectively the ride is certainly worse.

Richard

[KevinS]

I guess you will have to shoot yourself. I have seen this post many times, where people think that the sway bar will only effect the ride if it hits one side (“axle”) of a bump at a time, but randywebb is right (finally someone who knows what there're talking about). Think about it, if the job of the sway bar when pressure is applied downward on one side of the car is to produce an upward force to counter act that force and at the same time try to push down on the otherside (that force has got to go some where especially when tied together by a steel beam) so it will try to push down on the other side of the car. If the otherside of the car is also trying to be compressed then it will result in a not so nice ride. This is simple to think about but very hard to write, I hope I have explained it to some type on comprehension.

[911-32]

Maybe I am just (still) stupid (and at the risk of hijacking the thread), but I still don't get it. Think of a rear sway bar - its basically a solid steel bar across the car mounted in bushes so it can rotate, linked to the trailing arms with its own trailing arm type arrangement. Think of it as a very wide rear-facing "U" if you like. If both rear wheels hit the same bump and the rear suspension compresses by the same amount on either side, then the sway bar just rotates (relatively - ignoring friction/stiction) freely in its bushes. If the suspension moves the same amount on each side then the bar rotates by the same number of degrees on each side and there is no twist thru the bar. The sway bar cannot apply any force in any direction unless it twists. Imagine grabbing both sides of big "U" - if you move both sides of the "U" in the same direction it does not twist. If you move one up and one down it twists (and force is applied).

In simple terms, the sway bar can only twist if one side of the suspension either (i) compresses more than the other or (ii) compresses while the other side rebounds (and vice versa). It is not for nothing that sway bars (US terminology) are also known as anti-roll bars (ROW terminology). If what you describe is true then then an anti-roll bar has no roll reducing effect - which is demonstrably, empirically and even anecdoctally incorrect.

HTH
Richard
(hoping not to be shot done in flames)

[KevinS]

You anology of a u-shape is good and I imagine with a good sway bar they work that way. I'm only talking from experince when I've disconnected my sway abr on my Montero when off roading. Wheel travel is greatly increased, especially in the downward direction. Ride is much better but cornering s*cks. My Montero has rubber bushing which I think inhibit movement of the bar to rotate freely when hitting bumps with both side at the same time.

[911-32]

I guess this means I was right after all !!!