Well, here goes on seeking advice and comments on another item I need to possibly change. I just ran my car around for the past two days and it seems I have built a perfect racing suspension which is not ver good for the road. At my age I would like an excellent handling road car. The suspension I have does not allow any movement in it and when I do hit the "frozen ice cracks in the asphalt" it does transmit the bump through out the car. I even put about 100# weight in the front to equalize and see if it would cause the suspension to have some movement. Boy, do I have an excellent race suspension.

What do I have????

The front consists of a completely rebuilt/new suspension components including rack and pinion, 21mm after market sway bar, 22mm torsion bars, koni inserts red set on light suspension, etc. The suspension I have just listed causes the front end to move when going over a rough surface and appears to move around on me.

The rear suspension consists of rebuilt/new components including 180# springs on adjustable perches, Koni Red adjustables set to lightest, etc.

The front and rear suspensions are mounted on Elephant Racing Bronze inserts with zert fittings, new hardware bolts, new ball joints, etc.

Where I need comments and information is regarding any possible changes involves the front torsion bars and the rear springs.. Any comments/advice regarding the rest of the suspension that may need changing would be appreciated.

I am thinking of changing the front suspension to 19mm stock originals to lighten the stiffness and possibly give more movement in the front end. The rear would be changed to 140# springs with the rest of the suspension remaining as built. I could possibly go to the 100# springs if deemed necessary.

I need to find out where I can source any parts needed such as the torsion bars and springs. I may have original 911 front stock torsion bars and 914 rear stock springs in my parts bin.

Do you think I should return everything back to original suspension???

Car is powered with 3.2 1987 Carrera Sixer with a "Doc Evil Built and Blessed" 901 transaxle.

Need advice/comments. What do you think????

Thanks,
Steve

I'd start with the obvious and only change out the Torsion bars, (back to stock) and use a 140# progressive spring in the back. Leave the rest of it as it is, then see how it feels...

I've got that setup on my car, have run it for years and feel it's a good balance between drivablity and performance...

I like your information and advice. I do like a stiff suspension but one that moves. I used my present suspension on an earlier 914-V8 I built a lot of years ago (1980s) and was very happy with it. The difference today is I have virtually eliminated any body flex via stressed longs (length and side) and critical welding in the unibody. The rear suspension and shock points have been braced and welded. Thus, I need more movement in the front and rear suspensions.

Please keep the info/advice coming.

Thanks,
Steve

Is the steering puck a delrin part? If so, that will transmit all the smallest bumps up the column to the driver as well. You can replace the original worn puck with 2 Type I pucks from a VDub, they should be the same thickness when put together (slight modification required). Check and see if that was upgraded to Delrin qhen your steering rack was rebuilt.

You can also pull your seats (if stock) and have an upholsteror thicken the bottom cushions to help as well. Use Dynamap or a spray on dampener in the soors to deaden the noise as well...

Learned long time ago. Big torsion bars or big sway bar, not both


Disconnect sway bar and take it for a drive then determine if you have too big of a torsion bar

I personally have two sets of rear springs/shocks. 180# for track time and 140s for driving

best all around combination for a six. . rears 165 progressive springs, and stock 911 19 mm front torsion bars, and a 19 mm front sway bar. . plenty stiff for nice cornering but won't beat the fillings out of your teeth. .

Thanks for all the expert and respected advice. The ability to clear items and thoughts through this board is one of the greatest assets we have as members.

I will be changing the rear springs to 140# and the front torsion bars to 19mm. I will keep the 21mm sway bar for now and determine what is needed after changing the suspension items. The sway bar was run disconnected and the front torsion bars are too heavy for the stressed and welded chassis (no body flex). Since I am changing the basic elements to match suspensions recommended and compared with other friends' 914s, I will keep the present sway bar until this next spring when I will have a chance to make the changes and drive the car. First snow and it is getting very cool; coming early this year for the Arizona High Country.

I think the foregoing base suspension will be more to my liking and my old seventy year old body will like it better. I will be keeping the 22mm torsion bars and the rear 180# springs for the time being but will eventually get rid of them.

I want a suspension that will not pound me to death, but is still very firm and handles well on the high country roads of Arizona, Northern California, and Southern Oregon. I think based on your advice we have come up with something I can use and live with for spirited road driving. The only item I may have to change in the future will decrease the size of the front sway bar.

Thanks for your comments and advice; very much appreciated and will be used.

Steve

This issue has been one that I have been very concerned over. As my car is moving forward in its build I have thus far decided stock F&R sway bars (yeah I know), torsion bars, and likely fittings and joints. I will have the spindles raised about 3/4" on the struts to allow the car to be lowered a bit and turbo tie-rods. What I have yet to figure out is the rear springs (maybe 140's after reading this thread) and shocks/strut inserts. Car has red Konis on the rear now. I was actually thinking that Bilsteins on all 4 corners would be good. I want it to be softly firm for street driving and not rattle my teeth or require a kidney belt.

I think if you are building a road car you will find suspension items close to or similar to the ones we have discussed. The suspension system as I mentioned is one I built when building a very early V-8 car and I liked it for that purpose. It handled the higher center of gravity and still felt like the car was still with you. In that body I had good body flex, in this car I do not have any body flex. To get more movement in the suspension items I knew I had to change torsion bars and springs, possibly the front sway bar. I did some rough engineering calculations and came up with what our friends have suggested. As I mentioned there are several cars around running somewhat this same change suggestions and enjoy for road and some racing.

I could not find what the setup was for the original Sixers but they are probably somewhere in the area of what has been suggested here. Eric's recent new completed ride justifies an excellent example for making these changes. Racing is one thing, and road driving is another; somewhere it is nice to blend the two together to get the best of both worlds.

Funny part is that I do prefer Bilstein shocks which I have used to great success on several Alfa Romeos' I have owned. I enjoyed them in spirited road driving and then some. The Koni's are fine for the 914 and these I have set on the lightest setting for all four corners.

Look at the advice given here, see what the original setup is for 914-6, and ask different people about what you need to accomplish your driving goals.

Have fund and do make inquiries before making purchases. Be sure and happy in your mind before purchasing. You can see I am using a system I used earlier and assumed it would meet the same needs that I had 20 plus years ago. Now I have to make the changes which this particular car is telling me it needs to meet my present and future driving demands.

Use this thread to explore and determine what equipment will be needed for you and your car. Information may help others doing builds and save unnecessary costs.

Good luck and have fund in doing your build.

Steve

Hey Steve! I'm sure you know the balance between shock dynamics and spring rates is a narrow window. I think you can get the best advice from Chuck @ Elephant, Jason @ Paragon or even Renegade. I'm sure all have software that will take the guessing out. You just need the corner weights for them to plug in.

In theory, I wonder about progressive springs when the shocks are set to the springs. As you said, you want some movement.

Hey, Milt,

Great hearing from you and you still visit from time to time. Still building the 914-Sixer project and now making changes to fit my "senior citizen" needs. Still in Flagstaff and will be moving to Oregon next year. Another need of "senior citizen" requirements.

I like your suggestion and will followup.

Steve

Nothing over 19 up front both torsion bars and sway bars. Even if you do have a 19mm sway bar, you'll probably want to adjust it out toward the ends of the arms. I'd frankly look for a stock 914 torsion bar or 914-6 if you have 911 arms.

140s have always been a classic in the rear.

Love the Konis on full soft.

thanks, Eric, for your inputs. I have found 18mm torsion bars from an 1986 911 Targa which will be going on the front; appreciate your input on both the torsion bars, front sway bar, and 140# springs. I have 140# springs coming in the next few days.

I agree with you regarding nothing more than 19mm for sway bar and torsion bars. I will keep the 21mm sway bar for the time being to see what I have when I replace the springs and torsion bars. Need to run it with the sway bar adjusted all the way out towards the end of the sway bar arms. I am hoping this will soften the front enough for suspension movement. We shall see next spring!!

Thanks again, Eric.

Steve

Agree. Keep the 21 but adjust it full soft. Good luck.

You don't mention tires, what are you using?

Karl brings up another good point. I'm running 60 series but, some may not have the luxury of wanting a more vintage look. They help.

Sorry for the multiple posts. Just began reading in earnest to get a little more detail on your wants and needs:

For the above question - 17.8mm torsion bars and rubber bushings on the front with no anti-sway. Factory sixes never came with anti-sway bars. They had a stock 914-4 torsion bar spring weight with 911 spline count on the bars. Why they didn't just use 914-4 arms is beyond me BUT, I believe they spec'd front ends complete as I've seen a factory video with the entire front end being bolted in at once. Seeing as how the -6 basically had a 911T front end, this may be why (still doesn't explain how and/or why the -6 received a 914.351 part number on the strut though. That said, I've always felt a anti-sway-bar is a "must" for a 914.

The rear had 100lb. springs vs. 85-90lb. on a 914-4.

Given your driving requirements in the very first post,



I generally recommend a stock anti-sway bar. The current problems I think you're having in order of importance are:

1. Torsion bars. It seems like you're on to this and the 18.8's (factory 911 19mm bars) should help. I would even "seriously" consider finding factory 17.8mm 914-6 bars for what you are desiring. Think about it, this is your spring rate for a street car. It really has nothing to do with making a street car faster... just bumpier.

2. Anti-Sway bar. Again, set what you have on full soft but you still may have issues here. The main objective of this piece is to transfer dynamics from one wheel to the other. What you are looking for in a street car is a balance between get rid of the "Chris*Craft" lean in the corners and pound my fillings out. I have that one year 18mm 930 bar on both my cars and I "love" them. On the 914 I use Tarretts RSR arms which actually have a couple more holes in the end over a factory RSR arm. Mine is set "next to the last". What many don't realize is sway-bars can contribute greatly to an uncomfortable ride. I almost put this as #1.

3. Bushings. Love the Elephants and have them on both my cars. After driving both the 911 and the 914 on Elephant bronze I would "strongly recommend" Elephant rubber bushings for a street car. There is "no mistaking" the fact that you are now missing that rubber cushion between the cars suspension and the chassis. Yes, the suspension components work freely and much more efficiently but, little things like freeze cracks, sewer covers and driveway aprons will now "announce" their arrival. So you're giving up that mm here or there in the flex of your suspension but, that's they way it was designed by the factory. That design lasted 30 plus years unchanged and, the stiff bushings are simply not a requirement in a street car... in fact, I'd go so far as to say (in your case) they are a detriment.

I ramble because I think a lot of people could learn from this. There are a few people here who race their 914's regularly. The rest will generally drive them and participate in an occasional autocross. Over 30 years of 914 ownership has taught me that you really can't stop the "bigger-is-better" mentality, you can only hope to educate them. The suspension on our 914's is truly amazing right out of the box. My only critique (as mentioned above) is the lack of a mandatory anti-sway bar. Every single car should have had a 15mm bar installed at the factory up front at least. Read the reviews from 1970. Your front suspension is nuts and bolts identical to an iconic Porsche 911R, 911RS, 930 with the exception of a spring rate developed specifically for our cars. Think about it, that's super-car status.

Bottom Line - A stock 914 suspension is very, very, very good right out of the box. Add a well balanced anti-sway bar and it's fantastic. Use that as a base line and ask yourself what will this new "widget" do to my ride:

Solid Bushings - This will eliminate fractional inches of suspension movement while forsaking ride quality. Is this wanted/needed? [ ] Yes [ ] No.

Anti-Sway Bar - This will eliminate body roll while forsaking a smoother ride (remember... there are multiple levels to choose from here from 12mm to 22mm. Factory was 15mm) I really think this is a "must have" item but at what level? Is going beyond the factory 15mm bar wanted/needed? [ ] Yes [ ] No.

Heavy Torsion Bars - These will give you a harsher ride on the street while giving you a more predictable ride in a full race/track situation. As above, there are many variations. That's one of the benefits of owning a Porsche. I can't think of one benefit for a street car. Put your normal Jane or Joe in a stock 914 and drive them down a city street and ask them what they think. 9x out of 10 you will hear the car is already fairly stiff. Is this wanted/needed? [ ] Yes [ ] No.

The cool thing is; we have options. You may want a hair more spring rate or anti-sway bar. You can pretty much tweak to your hearts content. I'll stick with my original suggestions but keep in mind, 1mm in torsion bar rigidity can be a big difference in ride quality. I'll reserve the fact that you may even want to go back to 17.8 and a smaller sway bar.

Now this thread has developed into an article of excellence coming from our members. It has a lot of information and different elements fo digest. Excellence based on Excellence!!! I had forgotten about the classic thread(s) this board has listed which everyone should read and follow.

Here we go: I am changing the front torsion bars from 22mm to 18mm ones which should change the front spring rate; front shocks set on softest position; 21mm sway bar set to its softest setting (will probably change this later to follow the above advice); the Elephant bronze bushings with zerts will stay; tires will be changed to a higher series such as 60, 65 or 70 which should give a softer street ride.

The stock rear sway bar may or may not stay; the rear springs are being changed from 180# to 140# for evaluation; Elephant bronze busings with zerts will stay; tires will be changed to a higher series such as 60, 65, or 70

In sum, the new base line for evaluation involve changing the tires series to a higher rating allowing more air; front sway bar set softest, change torsion bars to 18mm, change rear springs to 140#. This will give a new base line to determine whether the front sway bar has to be down sized, rear springs have to be taken to 100#, and eliminating the rear sway bar. I have all these parts so the changeover should be relatively painless. Let us see what the next level of these changes brings us.

Someone mentioned tires. I am currently running 911 Cup II series 17 inch rims; front tires are 205x55x17 with 7 inch width, rear tires are 235x50x17 with 9 inch width. I would like to go to a higher series such as front 205 or 215 x 60 or 65, and the rear 235 or 245 x 60 or 65.

Great information. Thanks

Steve

You should love it with those changes.

I didn't know you had 17's. That's going to be another challenge. Man when you go in... you go in all the way don't ya?!?!?!

You were probably apologizing every time you ran over an ant!

Consider 15's or 16's (hate to say it)

Yes, I really have enjoyed building this car and making changes as I go. Sometimes I build and find out different things via performance, driving, etc. Then make the necessary changes all the while working the car down to driving equipment I can enjoy in my second, third, or . . . . . . . .. .childhood.

I know I am going to enjoy the changes I mentioned. Eric, when I saw what you had on your car I just knew I had to investigate and make changes to my car. Still enjoying the building.

Now, let us go into the "challenge of having 17's". Let continue the discussion involving the tires. I think I can get excellent tires in the 60 or 65 series but maybe someone has a suggestion on tire makes, ratings, performance, etc. I am playing the tire situation as if the car has a top end and a performance level as the mid 80's Carrera, etc.

Yes, when I get a "sickness, I do go all the way". I started out with information from the board including the corrections I making today. I had built a V8 914 many years earlier but it did not handle like I wanted. It seemed to handle like my old 64 Vette which means it was only good in the straight line; I wanted a car which would handle with quickness and agility. The V8 wanted to throw the rear end to the opposite front corner from the way I was turning. In sum, it sat for 10-15 years with 300 miles on it.
The present suspension on my current 914 comes from that V-8 914.

When I drove the present converted 914-Sixer (1987 911 Carrera) with the present suspension and 17inch rims/tires, I knew I had a car which would satisfy me even with the heavy movement. You have to remember I built the car with all the stressing etc from information on this board and I came up with what I would call a "perfect race car" operating on the roads. The car stayed flat over many road surfaces and it was a thrill to drive. Only on rough roads did the front end move laterally 2-4 inches thus making this car dangerous for highway road driving. This thread was started for information since I knew I would have to de-tune a "racing suspension" to one that was highway worthy.

There are also a few other changes I have made to the car which may surprise oneself. 911 Carrera heat exchangers, 911 oil tank, different type of front oil cooler, 911 dash and instruments, vacuum gage for troubleshooting, etc. to mention a few. Oh! Yes, I do have 911 brakes all four corners including the e-brakes, and flared fenders all corners.

Ok, Eric and others, let us consider the need for changing from 17 inch to ?????. Is it because of the ability of larger series tires being able to fit under the fenders? Is is because of inner and outer clearances? Is it because you cannot get the higher series tires in the correct performance rating needed for the vehicle?

The ants have become my friends and we ride together in the car to where ever they want to go; mostly, they just go along for the enjoyable ride!!!!! LOL!!!! A modified 914-Sixer is a great ride even with the present heavy suspension.

Ok, gang, keep the info coming and you are helping me make this mechanically one great ride and high street performance level.

Thanks,
Steve

Eric, Admins, et al,

I recommend we move this thread to a historical folder as a Top InfoU instruction guide for "Suspension Upgrading and Downgrading" how-to.

This info would be great for all searching on the subject, and has more detail in a small format than I have found so far in searching here to date (pictures aside).

Thx,
Dave

The sidewall you see on my car will give it a much more enjoyable ride. If you put that 60s profile on your 17s it will look like a monster truck.

I like 15s for what I built... a vintage reissue vehicle. The people that follow the line of thinking that the sidewall will help with comfort will usually fall into the 16" camp. There are more available tire sizes to choose from there.

Keep in mind, every inch you add (not unlike torsion bars and sway bars) will eliminate more sidewall making your ride more harsh.

I agree that the increased side wall will give you a more enjoyable ride. I still have adjustable perches in the rear which can compensate for the increased height. The front has adjustment to the torsion bars which can adjust the ride for the increase in height. Ther car has a nice profile and slight rake on the 17s; the key is how much increase in series can I add to give me a softer tire ride all the while making sure the tires has clearance around each wheel well and in the turning radius. I may be able to go only one or two steps above the present tires but for information I will be talking to the tire manufacturers/suppliers.

I can live with the rear having 140# springs and perche adjusted along with the 17s as long as I can get a little more sidewall underneath me. I feel the rear would be solid and would not have a tendency to leave you when and whenever. Definitely need more information to get a realistic answer.

The front will have 18mm torsion bar with the 21mm sway bar softened to maximum. I can always change the torsion bar to factory 15 or 16mm ones and definitely change the sway bar to a lower level. If I can only get one or two steps above present front tires, I will next consider these changes as necessities.

If the above indicates the 17s have to go for 15s or 16s, then we will make the change as needed. The changes along each stage will be based on valid inputs and information for members of our board. You can see I am trying to setup each change stages based on feedback from the car and members thus giving everyone understanding on how to either upgrade or downgrade. Main thing is costs can be eliminated by doing all your homework with advice, guidance, and feedback. Does not cost any money to ask.

Any more advice is deeply appreciated.

Steve

The final update on my car suspension will involve changing the springs to 140# without any rear sway bar (hope to keep the adjustable perches in rear) and all the adjustable Koni shocks adjusted to softest setting. The front as mentioned before has been changed to the 18mm torsion bars and 21mm sway bar set on softest setting. The tires will be mounted on the Cup II 17inch rims and will try to step up one or two series (55-60 front; 50-55 rear). Currently running front 205/50-17 and 235/40-17 rear.

I ran the change in the front with the sway bar in rear disconnected and 180# springs. I could live with this suspension with the increase in tire series, but still a little too heavy.

While waiting for the 14# springs to come in, I put on an old set of 80# to 100# set and this did not seem right, maybe a little soft even for my needs.

In sum, I have settled on the 140# springs in the rear without any sway bar. Keeping the 17inch rims with increased size in performance tires probably 55 front and 50 rear. All four corners will have Koni adjustable shocks, maybe adjustable perches in rear.

I have found with the forementioned setup, I can still feel the road and the suspension is working. Remember, the car has been welded and stressed in critical points so that all body flex has been eliminated. The suspension needs to work and I think the suspension mentioned will give me what i want in the car handling. All suspension points have Elephant bronze on all four corners.

I like the 140# springs in the rear.

Now just playing with the suspension adjustments. I can still feed the freeze lines in the road when I hit them dead on with both tires at once, but angling across them gives me a very comfortable crossing. No jars or unexpected movements.

I will not use a sway bar in the rear for normal and spirited road driving. It seems to match up with LSD or locked diff's, not the normal differential. With the rear sway bar detached, the suspension seems to be softer with the 140# springs but is willing to follow the front with minimum sway or related movement.

As "Bugs Bunny use to say, "That's all, folks!""

This thread and the contained information is a great present for my birthday in November.

Thanks for all the inputs and advice,
Steve

Sounds like you've dialed in a winner!

Thanks, Eric. I believe I have found the winner for my suspension needs. We will continue to experiment but within the realm of what I have described.

Steve

good read.

This is great stuff! I am always looking for info as I am in the process of building a sixer with a few upgrades.
Eric, what wheel and tire combo are you running? I have 7's and 8's x15" to install or all 8's. Right now, stock suspension pieces with sway bar mounts added while it was apart. This car is an M471 look alike project.
Bill

Hey Bill,

How's the project coming along? 7's and 8's (15) on mine. 215/60 and 205/60

It's getting there! Painting just finished, need to sand and buff out. Then the reassembly begins. I need to get started on the engine and trans before too long. Hoping to have it done by summer..