Need Help: Suspension Options

[scolson]

This is my initial message to the 911 S Registry.

I am restoring a 1973 911 S and I am contemplating suspension options. The car is stock has been sitting unused for some years. When done the car will be lowered slightly (to European ride height). My goal is to have a car that handles exceptionally well on the road (no track), yet rides comfortably enough for my wife to not complain too much.

The suggestions have I have received to date include:

Updating the factory Koni's to Bilstein's (any Boge Struts out there?!).
Upgrading the Torsion Bars to 21 MM front and 27 MM rear
Replace all original rubber bushings with rubber bushings from either Elephant Racing or Netrix
Update the original sway bars to front 76-77 Turbo through body type and rear from a 74 Carerra
Replacing original spring plate with an adjustable spring plate
Turbo Tie Rod Kit

Still others have said...replace the rubber, use the adjustable spring plates and leave the car alone.

Any suggestions?

I appreciate the help!

[Tom F.]

You'll get a lot of opinions, many of them valid. I have a Bilstein equipped 73 Targa and a Koni 'Classic' (the red ones) equipped 71 coupe. My 73 is all stock suspension, with factory sway bars. My 71 coupe is modified with a 3.0 liter motor. The 71 coupe went through several suspension modification attempts, before I acquired it. It was, in a word, a mess. Here are a few of the things that I learned in making it right.

I prefer the Bilsteins, but I am happy with the Konis that came on my 71. The main drawbacks of the Konis, IMHO, are (1) it is easier and cheaper to get specially valved Bilsteins (probably a good idea, if you are making a big change in torsion bars and going with raised spindles, for instance) and (2) the Konis may be a little harsh in Targas, which generally have more rattles and flex than coupes. The long and short of it is that I wouldn't spend the money to change yours, unless they are malfunctioning.

Again IMHO, the only change from stock bushings that I would consider are the Elephant polybronze, which I haven't tried in my car, but I have been in a car equipped with them, and thought they worked well. I did not like the Neatrix, and I got better results with a decent pair of used adjustable spring plates, with original factory rubber, on my 71.

As far as torsion bars go, my 71 came with the Turbo rear torsion bars (26 mm) and a ride height that was too low. Going with stock front torsion bars and SC/early Carrera rears (24 mm) at a sane ride height with my 3.0 liter equipped car worked well. I have 18 mm factory front and rear sway bars, which I definitely like better than the stock 15 mm ones. Spend money on corner balancing.

Certainly, there are upgrades with much larger torsion bars, raised spindle, specially valved Bilsteins, and so on, but you should only look at a package that someone with experience (Steve Weiner, say) has put together. My opinion is that the factory suspension pieces work best, unless you are prepared to spend serious money. Even then, you may end up with a ride that your wife doesn't like.

Finally, search around this site and Pelican. You'll find a great deal of useful guidance.

[John Z Goriup]

Welcome to the Early 911S Registry !!

Your 6-point "recipe" above sums up a reasonable, effective program to achieve your goal for a comfortable ride with significantly improved handling.

Euro ride height is very practical for the road, retains sufficient wheel travel, avoids bottoming, and you can get away with just adding the steering rack-spacer style of bump steer kit.

1. I recommend Bilstein shocks. Quality product, very long life without change in performance, excellent service, and perhaps most importantly, readily re-valved to accommodate your exact performance profile preference.

2. Your torsion bar choices are just about perfect. (You'll be very happy with the hollow Sanders bars from Elephant Racing) If the front proves to be a bit too stiffly sprung with the 21mm after-market bars, I suggest replacing them with OEM Turbo 19.8 mm bars for a very good balance and ride.

3. All new OEM rubber bushings at all locations is the biggest single improvement you can make.......provided you choose new OEM-style rubber bushings. My suggestion, avoid Neatrix.......shorter useful life and noisy. Also - replace ALL rubber suspension bits, incl. top strut camber bushings and trailing arm bushings.

4. I am firmly convinced that Smart Racing anti-roll bars are far & away the best choice. Adjustable, instant reaction, wide initial choice of bar diameter, they last. Important detail : be sure to install WEVO anti-roll bar cast steel consoles. The combo of SR anti-roll bars and WEVO brackets will be the most expensive part of your suspension options, but well worth it. Huge difference in handling over any combination of stock bars.

5. I'm not at all sure of the need for adjustable aftermarket spring-plates for a road car. The later OEM Carrera-style spring plates are perfectly acceptable and a lot less expensive to purchased used. The after-market adj. plates are great for a track car, but serve little purpose on a street driven machine. Apply the $$$ savings to the sway bars in Point #4.

6. Turbo tie rods: Yes, essential

Give a lot of thought to your tires. My recommendation is to avoid the 50 / 55 series rubber and stick with the more flexible, taller aspect ratio tires. The above set-up has the potential to provide a smooth, comfortable & enjoyable ride. No point compromising it with the wrong tires. Also remember the effect tire diameter has on gearing.

As a last thought, have the car professionally aligned and corner-weighed. It's well worth it.

Good Luck,

JZG

[jameshtaylor]

Second John's comment about tires. Your choice here is crucial. 60's will yield a pleasant street ride. Going to 50's will greatly improve handling but at a fairly high price. Changing out the stock rubber is probably the best thing you'll do in terms of immediate impact. For street use I'd add later stock 20mm front/18mm rear sway bars and save some money. You can pick these up for nothing and they make a nice change in corner roll. Adjustable sway bars for the street, along with adjustable spring plates? Nice, but a waste of money. When you are finished with your changes get a good alignment and corner balance and enjoy.

[Chuck Miller]

scolson,

I agree with all that's been said...

I would add the 'rack spacer kit'

Can't stress the importance of a good 'set-up' enough ...
Once you replace the parts and tires, the corner balance and alignment is EVERYTHING.

If you give us your general location, we can possibly give you a recommendation for the set-up

Cheers and good luck

[Flieger]

Yes:
Turbo Tie-Rods
(Factory) Adjustable Spring Plates
Good Tires
Good Alignment/Corner Balance
Your torsion bar choices

If you want to go further than the factory rubber bushings, then maybe:
(I am happily using these)
Rebel Racing A-arm bushings
Smart Racing rear spring plate bushings
Monoballs for the front strut top and rear trailing arm

Not worth the money:
Bilstein struts

The aftermarket bearings/bushings allow the suspension to move with less friction and no binding so the torsion bars effectively feel softer. The setup I have is no-maintainance, like the rubber. The lifespan will not be decades but should last long enough for me. The Rebel Racing bushings are lighter than the Polybronze. They are also cheaper when you factor in the spherical washers cost $35 but the ER low-friction mounts are much more.

http://www.rebelracingproducts.com/S.../Steering.html

[CidTito]

I need a little bit of help related to my 69 Targa suspension. The car has factory front but no rear sway bars, but in my quest for "911 truth", I came across a factory 15mm with factory drop link earlier this morning. I am in the process to clean it up and maybe install it. having it might be good when i am shooting around cones for Autocross in 2013. I am also not exactly complaining about my car's performance for open roads, being a targa and the 3.2 with 901 tranny, its plenty fast... and strong.

The car has front Boge and rear KYB. It is running 16" Fuchs. I am not using turbo tie rods with it either, which I wonder to put in. The car also has the upgraded aluminum trailing arms and in order to connect the control arms to them, Ill need to bolt in a pair of aftermarket sockets.

Question: being a long wheel base Targa... is this a good direction to go? I just find it interesting that it never had rear sway bars. I heard that also, maybe having a secondary set of roll bars would be better recommended, but that too seems a bit questionable as there is a competition for space in the thing as it is.

Can anyone help?

Tito

[Jens]

Mr. Olson, welcome to the Registry. I'd recommend coil-overs, but then again, I am a little biased.

All great input from the above comments, Chuck at Elephant makes really good components. I'll also chime in that alignment and corner balancing is a crucial final step.

[Mr9146]

My car:

SC front end (Blistein struts)
Smart bushings
930 tie rods
SC front sway bar (19 or 20mm)
19mm front T-bar
Bilstein HD inserts
Elephant bump steer kit

Rear:
24mm T-bar
SC spring plates
Smart bushings
Elephant control arm monoball at torsion tube (one of the best upgrades for alignment, terrible for noise transfer)
G-50 Carrera rear sway bar (22mm)
Aluminum rear arms (it's a 74, but I had the same setup in my 70)
Bilstein HD rears

Bogue struts will work fine, but I'm not a huge proponent of Koni's stuff because I feel - and it's all about "feel" isn't it? - they are too "smooshy" on compression and too "bouncy" on the rebound ... despite being adjustable.

I've installed most of the aftermarket manufacturers' bushings (Rebel, Elephant, Smart) and all are very good at what they do. The Rebel and Elephant stuff, I feel, are held back by their rigidity in fitment ... in other words, if your car isn't 100% perfectly square - and after 30-40 years of hard road abuse not all of them are - then they don't fit and/or function properly. The Smart parts allow for a bit of wiggle room and are designed to be custom fit for each application. To date, I've never had a problem with them and I've been able to use them in places where Rebel and Elephant have failed due to the car(s) not being 100% jig straight perfect. And, yes, I know we'd all like to believe our cars are perfect but, surprise, they're not. They are living creatures ... ever cut the cage out of a seasoned racecar? Don't. The doors might not shut afterward.

My recommendation would be to mix and match the best of ALL the manufacturers ... no single supplier got it 100% right, but put together a "Think Tank" and you'll find a fabulous result.

[Jens]

Listen to Marco, that's what I meant to say.