A friend has told me, rear sway bars are suppose to be bad and many people remove them. He says he has heard this from others.

Are rear sway bars good or bad? One of my 914s has the front factory sway bar but no rear sway bar.

I have purchased front and rear aftermarket sway bars for one of my vehicles which currently has none, though I have not added them yet.

I have also purchased a rear aftermarket sway bar to put on the one that has only the front factory sway bar.

Since 914s were designed by Porsche, I find it hard to believe they made a mistake on suspension and handling. These are the things Porsche is famous for.

Does anyone have experience with and without rear sway bars and knows.

Thank you.

My 72 has front and rear and without the rear, it is loose in the back end. That being said, my 74 has a front but no rear and it stick like a slot car. I think it all has to do with how you set the car up cause they work both ways. All depends on the driving you will do. I drive local canyon roads not the track.

I was on a drive recently and the rear kept feeling loose. When I got home, I noticed the rear drop link bushings had worn and the bar popped off one side. 4 new bushings later it sticks like glue again.

I am sure others will pipe in, I am no racer so the physics of it all is not my cup of tea.

Front & Rear Factory Sway Bars with Koni Sport Yellows adjustable on all 4 corners.



Sticks like glue, ask @robarabian as he took the pic.


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Good.

Lots of folks on here say to remove the rear bar. I disagree. With the rear bar, you can run softer springs in the rear and get the same handling as if you put stiffer springs on the rear and removed the bar.

Betty's car was dead neutral and would corner like it was on rails. It had both front and rear bars, and replacement springs on the rear.

Clay

- from a engineering design and tuning perspective that is exactly right.

Removing the rear bar without doing anything else adds a tendency toward understeer and dulls vehicle turn in.

Suspension all has to work together. Many people start out thinking if some is good, more is better. Oversizing everything isn't the answer. So if you add a rear bar, don't also go up in spring rate, at least not at the same time. Read up what each component does and how it will affect the car. Also think about how you will be using the car, your local roads and who will be your passenger.

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My car has '73-'74 front & rear (stock 914) sway bars. I have 140 pound rear springs, Bilstein shocks and Elephant Racing rubber bushings all around. Raised the front spindles 19mm and added the tie rod modification also by Elephant Racing. Stock torsion bars up front. My goal was to have a comfortable car that handled good enough for street driving and did not squeak. I think the car rides and handles just like I wanted and of course, no squeaks. Oh, I also have deep 6 Fuchs with 195x55x15 Yokohama tires. I really wanted a good summer performance tire that was 195x60x15, but could not find any.

Some racers might chime in here. I have had the rear tire lift with a rear bar on a tight corner once or twice on the street. I am not a track racer. I think they removed them for that reason and controlled the car from the front. You want rear wheels on the ground for more go and the front planted for more steering. It all has to work together. The ones that I know of that do race spend a lot of time in this area testing combinations and theory.
My first 914 was a detuned track car, front bar only, stiff springs in back. Drove great. I have since added a rear bar with no complaints. YMMV

great to make the four cylinder turn better, 15 front 16 rear Do not want to get too large with the bars unless you are racing

Front sway bar, but no rear sway bar, Installed 140lb. rear springs instead.

Front 19mm and 17mm rear sway bars. 19mm front torsion bars and 140lb springs in rear. Way fun.

That is exactly my point. You could put on softer rear springs and a rear bar. You would get a better ride and the same handling.


Clay

This is exactly right. Stiff rear springs plus a rear bar will cause rear wheel lift in tight corners and if you don't have a limited slip, you won't get enough traction to get out of that corner quick.
Which is why the rear bar has a bad rap with certain people.

If your suspension is setup to support a rear bar (as already explained above) the rear bar is very much beneficial. You can't look at suspension components in isolation, they all affect each other.


PS: I have run front and rear bars for 20 years on my car and wouldn't run it without a rear bar.

Probably would get BETTER handling.

A stiff suspension lacking compliance over bumps and road imperfections usually performs unpredictably, and degrades confidence.

The problem with this discussion on the street is the lack of hard metrics by which folks judge improvement or degradation. Most just slap on whatever “the recipe” is or what they bought and call it an improvement.

Using spring rate only for roll control is counter productive

Does anyone still sell rear bars?

yes

my 1.8 has stock rear springs and factory front and rear sway bars since new.

i think the idea was comfort with soft springs and handling with rear sway bar.

Thank you . This is the picture I see. The only bars that seem available are the occasional used ones, factory or sometimes a Weltmeister, and for new, an Addco. Maybe just haven't turned over enough stones, but can't find any other options. Even started looking into how to make a custom bar, but everyone says proper tempering of the metal is almost impossible to do at home. One would think that with the latest 914 enthusiasm over the past few years there would be a some nice aftermarket choices available. Would love a rear bar that was adjustable

Dan

I think if you post a WTB you will get offers. Get a complete stock one.

Rebel Racing Products shows a rear bar for sale... I just received their front bar (Tarrett), and the online form prompts you for either front or rear 09

I've always run a rear bar on mine as well - much better on track than without it and no wheel lift/traction issues. I did switch from a Weltmeister (which broke) back to a restored factory bar w/ new bushings a few years ago.

Looks like some nice stuff. I'd bet a dollar that those rears will end up being for 911s. A couple of their bars showed options for front or rear, and think the smallest effective was 19mm. No pics in any detail that look like a 914 rear. May be worth a call.

Dan

FWIW when I set up my 914 for SCCA and PCA racing, I tried a variety of suspension components including rear springs, and settings. And I experimented with and without rear sway bars. At my home test track, I reached a point where stiffer springs and no bar, and softer springs with bar produced the same lap times. But the car felt more confident with the bar, so that's how I ran it.

Not a black or white question.

Setting a suspension up is more calculus then arithmetic.


Maybe more like the Uncertainty Principle.

Set it up how you like to drive it. You don't state what you have or what you want it to feel like when you drive it or how you drive.

In addition to the possibility of rear wheel lift when using a sway bar, excessively-lowered cars can bottom out the bar with a loud "THUNK" and a near-infinite rear roll rate momentarily. You can guess that's not so good for handling.

It's not a problem for cars that have sane ride heights, but some track cars can run into it.

The suspension is a system. Changing one part of it affects everything. Changes can be good or bad or neither, depending on many many factors.

I liked how my car drove with stock rear springs and the stock rear bar. I also like it with 140 lb/in rear springs and no rear bar. But it is significantly harsher this way.

--DD

yes DD

i'm all for the factory getting it just right way back when they did it.

i have two cars which are way better than they should be.
a 74 1.8 914 with front and rear sway bars and stock rear springs.
a renault clio RS 172.
i meddle with neither.
even run the tyres they are supposed to have.
they give me pleasure in the form they were always in.

........for the street.

I've owned at least six 914/4s all with different setups on sway, anti-sway, torsion or stabilizer bars, springs, struts and shocks, stock, performance, adjustable and gawd only knows what. I've added slightly heavier rear springs to the ones that came stock b/c I preferred the stiffer feel although I did very little autocross or racing with them in which case I would not leave home without them being performance tuned and adjusted to my driving preferences. For just everyday street driving I found it was very easy to just learn to drive what I had and save my money for more important things that I always needed. You could always go with adjustables such as Elephant Racing or Koni or whoever offers. You usually can't go wrong with stock for street driving on summer weekends to cars and coffee. Search the many threads here on the subject and you will get millions of opinions I'm sure.

I drove around for about two weeks recently without my rear sway bar as I was awaiting new bushings. I thought the car handled better without it, until I reinstalled it, then it felt better with it on. I think it's largely psychological for most of us. In a blind test drive, who is able to tell for sure if he is driving a car with a rear sway bar or not? Probably only very experienced race, rally, and autocross drivers.

Ansbacher

A big thank you to everyone.

I have decided to add the sway bars. My moderate country driving will accommodate it and be more enjoyable.

Thank you again.

I think that is a good call. Besides, once installed, if you feel it is not right for you, you can always disconnect the end link and drive it.

I am running 140lb. rear springs with a 19mm front sway bar. Going to try a set of 19mm torsion bars in the front to replace the almost 50 year old stock bars.

Because you want more understeer? Because you want more ride harshness? Because you want to add more weight to your 914? Because you want more front roll control and don’t believe that anti roll bars are best used to achieve that goal?

Not trying to pick on you. Just using it as an example.

The whole point of this thread being - know what you are trying to achieve before making random trial and error changes just because someone else did, or because some vendor is selling it as an “upgrade”.

Superhawk, sorry I posted, didn't mean to piss you off. Didn't know you were suspension expert of 914 World! How are you supposed to know what works and what doesn't until you try it? 2 pages of posts and not everyone is running the same combination!

Not pissed off at all - just trying to help make the point that suspension tuning is not guesswork. Posted a great reference book for layman to understand how chassis tuning works and how to avoid guesswork. Moving up the from a stock torsion bar to 19mm is about a 50% change in spring rate. That increase in front spring rate will have the consequences I outlined - good or bad depending on what the goal is.

27 years as an automotive engineer focused on chassis (brakes, suspension, hubs & bearings, ABS/ESC systems). So I do have a bit of experience in the area.

As was noted - was simply using the example to reiterate a point. Didn’t mean to piss you off either. Just trying to help avoid trial and error guesswork.

This topic could not be more timely. This week I purchased a rear sway bar setup from @roundtwo to install on my 74. My car did not come with sway bars but I added a 19mm GPR/Tarett front bar two years ago. The front bar really helped to stabilize the car. I have the bar set to full soft with stock torsions, 100# springs in the rear and Koni Sports. After having an alignment and corner balance I really like the handling but cannot leave well enough alone and now it's time for the rear bar install.

Will report back after install and tuning.

Exactly, you didn't know how the rear sway bar would work until you installed it. You can read all the books you engineers can publish, but until I try the torsion bars on MY car with MY set up, I will not know it is going to work. It may make an improvement, it may not, but I have to install them to find out. No book is going to give me that information until I sit in the driver's seat!

I have to agree but need to say that @Superhawk996 helped me sort out some issues I was experiencing awhile back and he knows what to do. Understeer or over steer is a balance, and some like the feel of more or less. I have a slight understeer in certain conditions that I feel can be balanced out with the addition of the rear bar and the adjustability of my front bar. I would not trade the ride quality I have now by adding stiffer springs on either end. Cant wait to get the rear bar in action. Should be railing corners on Sunday.

@Brian Fuerbach

Thanks for the kind words. I remember that thread. Glad to see you working through your set up in a logical way, evaluating what you have, what you want to change, and making logical choices to move in that direction.

As stated by others in this thread, it’s a system. There is most definitely interplay to balance the front and the rear to achieve the balance that suits your desire. Guess work and wasted money doesn’t need to be part of that process.

This is why our cars have front and rear bars, and torsion and springs, all stock… we let Porsche do the testing and costly iteration.

@Superhawk996 , would love to discuss the halfshaft I just blew in our Chevy wagon… I did not check the four link or coil over alignment and after 136 miles it blew up

Will send you a PM for more advice.

[/quote]
Not pissed off at all - just trying to help make the point that suspension tuning is not guesswork. Posted a great reference book for layman to understand how chassis tuning works and how to avoid guesswork. Moving up the from a stock torsion bar to 19mm is about a 50% change in spring rate. That increase in front spring rate will have the consequences I outlined - good or bad depending on what the goal is.

*********************************************************************

It was all guesswork for Thomas Edison when he was searching for a filament for his electric light. Sometimes that approach works.

Ansbacher

Big difference between invention of a new technology and the application of a known science that is well documented.

Hate to date myself but 100 years ago Tom Green of Automotion did a huge amount of research and testing. It was mainly for autocrossing but he even produced a book/manual detailing the specs….it was stage 1-2-3 interns of set up.
His Stage 3 was 21mm front bar 180lb rear springs no bar. Then add 21 mm T bars. All the hottest cars in the Bay Area used that basic set up…….except one guy who ran a rear bar and CArrerra coil over shocks… very quick.
For the track I am still a no rear bar……but with today Hoosiers rear springs went to 400 to keep front tires planted,..
Just my 2 cents

Bar is in! Bushing on the drop link were hard to get on but once home have some slop. Is this normal?
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Mine has both. But with my elephant bushing suspension, I have full travel with my suspension. It seems to handle very flat. Front is the Tarret bar, rear is stock.

In the movie Rush, Nike Lauda tears apart the whole car and changes the suspension that all the high paid engineers designed but the car handled like shit. Theory is one thing, but the real proof is on the track. As they say, "you wont know until you have tried it."

Back when I first built my car in the dark ages, the advice was heavier springs and no rear bar, so that's what I did. 140s in the rear, and the stock front bar up front.

I have given thought to changing to a rear sway bar when I go 5 lug, but I'll need to figure out a new place for the remote oil cooler to go, since that will interfere with the path of the bar.

Its been about 12 years since I last AXed the car (and 5 years since I AXed any car), these days its been all trips and street driving. Maybe when the kids are out of scouts I'll have time to start doing AX again.

I've never felt my 914 was particularly harsh. But it is a lowered sports car and feels "right" to me with the bigger springs. I also don't have a ton of seat time in other 914s - and I don't remember the last time I drove a stock 914 for comparison.

Zach

Last night was the first drive with the stock rear bar installed. Drove my usual fun run out Santiago Canyon road to Cook’s Corner and back to Orange. Big 70+mph sweepers.
First thing I noticed is the steering was lighter around the corners and one hand was all that was needed to feel
comfortable at speed. The car feels a lot more lively but more controllable at the same time as the rear seems to follow the front track more closely. All I can say to myself is “why did you wait so long?”

Very tight corners like intersections are also better but the first hard one scared me a bit as I turned in like I had before, muscle it in and push through. That doesn’t work any longer or should I say is no longer required. Turn in is much improved. My front bar is an adjustable 19mm gpr/tarett set to full soft. Now if things prove to lively for me in the future I can stiffen up the the front to induce some push. Just going to drive it for awhile before making any changes. I cant comment on the stock front and rear bar combo but the 19 front on full soft and 16 rear feels right as I dont think I would want the rear any more lively.