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914forme
Okay is just me or do I over think stuff! idea.gif

Anyrate, the Welt 22mm is going going, gone - It is in the FS adds.

Colaman Racing to the rescue. But I needed to know some infor before I started. So thanks to Fred Puhn, I made up an excell spreadsheet to figure out my adjustable rate swaybar and what I had.

Here is the Weltmeister 22mm bar - the conversion was done over to inches. Notice the top number, I was running my bar full hard, about 3 inches from the center of the bar. That produces and effective rate of 150 Ft. Lbs of pressure. With out going into other factors just the most basic physics here.



914forme
Okay here is the colman bar I ordered, it is 1 1/4" solid bar. With 14 inch long arms, I am going to cut them down! Way it looks from the current setup, I would run at about 4" out on the arm. And it only goes up from there.
nine14cats
Pretty nice....let me get my wife and show her that other folks use spreadsheets too! Oh honey.........come here and look at this! laugh.gif

1.25 inch is ~31mm bar....Trekkor should like this thread. I had a 27mm Smart bar on the 914-6 and on the 911.

Pretty cool!

Bill P.
914forme
chairfall.gif

Bill this is for you all things being equal with the smart.

27mm Smart Racing Front Swaybar
nine14cats
QUOTE(914forme @ Aug 23 2006, 08:12 PM) *

chairfall.gif

Bill this is for you all things being equal with the smart.

27mm Smart Racing Front Swaybar


Thanks! clap56.gif

You do realize I will use you as an accomplice whenever my wife catches me crunching race car numbers.... type.gif

beer.gif

Bill P.
J P Stein
OK...so allow me to overthink this thing.
With say 250 lb springs up front, setting one of these bars to equal 250 lbs of twist would cancel out 1 inch of roll (suspension movement....static) from what ever movement you started out with. Loaded, to around 1 g, it would be twice that....rough numbers....very rough. So, do you know how much weight is on each of your front wheels, what your front spring weights are, how much suspension travel is available?
If you do, those AR bar numbers become useful.....but only to keep the front restricted in movement away from parallel to the ground. This also helps keep the car from running out of suspension travel, but that is the main job of your springs.

So, what do you set an AR bar for.....to keep it flat? Not me, I set it to increase/decrease over/understeer. Sure, it's nice to keep the tire as verticle as possible, but not at the expense of a bad push, for instance. If it pushes when you have the AR bar set, you have 2 options......decrease the front roll stiffness or increase the rear spring rate. If the front AR bar is set at full soft already, your options are very limited.

Things like front (not a problem to me) or rear (a stinker)tire lift enter into your AR & springs rates also. Then there's available grip. A car on street tires will behave one way. Increase your grip by 20-30% with Rspec/slick tires, your roll rate rises and you're readjusting both AR & spring rates (this assumes you have the camber in the tire that it likes)....*to keep the car balanced to whatever handling attributes you are most comfortable with*.

Anybody that has been down this road knows that the above is just a chunk of what it takes to get a car working to it's potential.....something I'm still working on. biggrin.gif
Borderline
Your 1.25 dia bar is about 8 times as stiff as my 19mm (.75") bar!! How do you balance out the roll stiffness at the rear to keep the car from plowing out in the corners? Are you going to super stiff springs or are you adding a stiffer bar? Thanks for the spreadsheet. I haven't gotten around to doing my own. I never ran the numbers to see how much difference the lever arm really makes. I am curious as to the fromula you are using. If you have the bar diameter and a lever arm radius, shouldn't the resulting number be in pounds and not in-lbs?? confused24.gif
914forme
Okay here goes the answers.

Bill, use me if you want I am know to be a bad influence on others.

J.P. - I was using the calculations to see where to cut the arms off at, they are heavy buggers. So I figure I needed a little less bar for future use, and a lot more bar for current use. I adjust my bar for balance and to correct certain tendencies my current setup has to do.

Borderline - Now I am no excel wizard which you are about to see, but the formula works. BTW, the last column calculates the inch pounds to Foot Pounds.

Here is the formula to calculate the bar Rates!
=SUM(500000*(D19*D19*D19*D19))/((0.4244*(A19*A19)*B19)+(0.2264*(C19*C19*C19)))

This is the conversion to Foot Pounds
=SUM(E19/12)

That one is pretty simple.

In the spreadsheet A is the parallel distance fro the bar to the pickup point. B is the length of the bar, C is the Arm length, D is bar diameter. It only works for bars of a constant diameter. So necked down bars it will be slightly off.

If anybody out there knows how to add the power of to an Excel equation it would clean it up, but the math is correct, logicly.

Now what kind of rear rates do I run. 175lbs springs, and a stock rear bar. Have not done the calculation on the rear bar yet. The rear bar is currently non adjustable. So I have to use only the front. I maxed out the Welt trying to find a good balance, I need a little bit more, so I am moving up large.!!!!
groot
Good discussion. Let me fuel the fire a bit.....

You should use your unsprung weights, corner weights, spring rates and motion ratios to figure out what roll rate (degrees/g sometimes called roll gradient) you have with just your springs, then add in the bar to see the change. One rule of thumb is the bar should account for 20-50% of your roll stiffness... I like it on the low end. Adjusting this % allows you to tune the amount of understeer in the car.

Then once you've figured that out you can take it a step further to figure out the amount of roll resistance at each end of the vehicle... this is called roll couple. The % of roll resistance on the front axle should be in the 60% range or so, tune to suit.

These #s are just suggestions that I've found some luck with and can be debated forever...

And of course, none of this matters if you run out of suspension travel too early like most 914s do in the front (because the spring rate goes non-linear).
grantsfo
It would seem to me that not all sway bar linkages are the same and would have differing effective rates depnding on how they connect to a given swaybar and suspension. Also how do you account for differing bar shapes and metal characteristics? I have never thought about this, but are all sway bars made from the same type of steel?

Could it be possible that one company's 27 mm could be stiffer than anothers 31 mm just based on steel used and linkage configuration?

It is interesting to see the assummed progression but I'm not sure how to use this data in determining setup?

Kevin brings up points I was thinking of too about preload and non linear aspects of the 914 suspension.
914forme
Yes it is possible that due to different metallurgy you can have a different rate off the bar. Some adjustable swaybars use this theory to make it adjustable, by changing the bar arm angle so as it rolls over to the flat side it becomes more springy, thus reducing the arms ability to transfer the swaybars input. None engineers terms here biggrin.gif

So yes in theory the data can be off from this very simple formula that figures all things being equal.

Somebody's 31mm might be weaker also if it is a tubular design also. For a tubular design the Wall thickness ( inner Diameter) determines the sway bar rate. A solid bar has no wall thickness in general theory. In reality they do have a wall, but it is very thin.

So the same bar, 1.25 bar with a wall thickness of .25 would rate out as this. So the inner diameter is 1.00 In this simple example.

I had to modify the formula to work these through.

=SUM(500000*((D47*D47*D47*D47)-(G47*G47*G47*G47)))/((0.4244*(A47*A47)*B47)+(0.2264*(C47*C47*C47)))
groot
Actually, a hollow bar's rate is determined my the outer diameter and wall thickness, not just the wall thickness. The inner portion of a solid bar really does very little to increase is stiffness. There are a bunch of simple equations to account for different shapes. Most bars are made of spring steel and should be heat treated to attempt to keep a constant rate.

The linkage of the bar is accounted for in the stablizer bar motion ratio... which is also a very important consideration. Good point, Grant.
914forme
Yeah that is correct, I misstated my terms above. I only play an engineer on tv. But the formula for the hollow bars does take into account bar diameter above, and works accordingly.

J P Stein
QUOTE(914forme @ Aug 24 2006, 05:13 AM) *

Now what kind of rear rates do I run. 175lbs springs, and a stock rear bar. Have not done the calculation on the rear bar yet. The rear bar is currently non adjustable. So I have to use only the front. I maxed out the Welt trying to find a good balance, I need a little bit more, so I am moving up large.!!!!


I use a 25 mm Tarret (effective 22mm) front AR bar. It provides plenty of roll stiffness.....but I don't use a rear AR bar. Neither the front nor rear inside tires lift off the ground during cornering. I'm presently working on an oversteer condition that (I think) has been made worse by heat cycled-out rear tires. I'm confident that there are enough adjustments to get back to a comfortable amount of oversteer.
Borderline
I ran my first AX in the teener last month and the car was suffering from a terminal case of understeer. The car was set up with front 22mm Tbars and a 19mm AR bar of my own design. The rear had only 160# springs. For this weekend I have added a stock rear AR bar and a pair of 175# springs (thanks again, Grant). From what you are saying I'm going to be pretty tailhappy this weekend.

Kevin: your rule of 20-50% AR bar roll stiffness goes against what I have read on other threads here in the past. Others have been proposing keeping the stock Tbars and controlling all the roll with AR bars. I'm not trying to be confrontational. I love this kind of talk! I first AX'd over 30 years ago in college and the theory then was that stock suspensions were so bad that the only way to fix them was to go to super stiff springs & AR bars to limit suspension travel. I've been away from cars for a while and now I'm interested to see if anything has changed over the years.

I sure have been having a lot of fun. the 914 is a great little car! mueba.gif
914forme
Boarderline, maybe maybe not, I don't know your combo. The 22mm TBs are large for my conditions. but that combo might be just waht you need.

BTW, did the calculations on a rear bar I have back in storage. The 11 inch arm length means these things should not have the effect you all say they do! I believe that my car rolls so much that I run into a suspension travel issue in the rear. And the Sway bar just adds to minimize the travel.

Why you say, Because the bar rates are so low, they should not matter in this senario.

First one is a 15mm rear bar
Second is a 16mm rear bar
J P Stein
QUOTE(Borderline @ Aug 24 2006, 12:43 PM) *



Kevin: your rule of 20-50% AR bar roll stiffness goes against what I have read on other threads here in the past. Others have been proposing keeping the stock Tbars and controlling all the roll with AR bars. I'm not trying to be confrontational. I love this kind of talk! I first AX'd over 30 years ago in college and the theory then was that stock suspensions were so bad that the only way to fix them was to go to super stiff springs & AR bars to limit suspension travel. I've been away from cars for a while and now I'm interested to see if anything has changed over the years.

I sure have been having a lot of fun. the 914 is a great little car! mueba.gif


The soft spring/ stiff bar thing goes way back. The proponent (first I read) at the time was Dan Gurney......on infinently adjustable race cars. A truck fulla springs,shox,bar sizes, vairable limited slips, tiar compounds & sizes will help out biggrin.gif
As time progressed, he added wings & things to his bag of tricks. Now Mr. Gurney is atop my short list of American racin heroes, but...these are pure bred race cars on a race track.
Just a smigen below him on this list comes Mark Donahue. Read his book
"The Unfair Advantage" and you will find a set-up guy that will do whatever it takes to make any car....Camero to F1 cars..handle. He gives a wonderful progression in his learning curve over 10-15 years in all kinds of cars.....again, race track cars.

When you get down to 914s, there are some limitations.....starting with a chassis that flexes in both pitch & roll...(prolly yaw also biggrin.gif ) which varies by car in use & abuse. Work at one end does not necessarily transfer to the other like one might think due to this..."feature". It also has a nasty habit of picking up the rear inside tire at some point...the more speed/grip, the earlier it comes.....rear AR bar or no. This is cureable *by working on the end that is fucking up*....be it stiffer springs or an LSD, for instance....or both. (An LSD will not cure a rear wheel lift, but at least the car keeps driving forward....till traction is lost on that lone wheel, then you spin....or take a run at it)
Then you need to work on the front to cure your push or loose condition should this arise. Rear wheel lift is a killer.

My focus is AX...not track racin. The 2 do not correlate set-up wise in my experience. An AX car has to rotate around a tight corner, but not get too loose on a sweeper.....slaloms are sweepers hooked together that keep changing direction.
Understeer in a track car is safe/wise. It is a looser in AX. I do what ever it takes to get a car set up to my liking....with varing degrees of success. huh.gif

Brad pushes the soft spring/stiff bar deal. If you think Brad is the greatest AXer to come down the pike, go with his thinking.
AndrewBlyholder
To clean up the Excel formulas, power calculations are done with ^.

3^2 is 3 squared, 3^.5 is the square root of 3.

Good discussion. One of my long term goals has always been to measure all the geometry of the front and rear suspensions so I could figure out the actual wheel rates produced by the springs and anti-roll bars.

I don't know if anyone out that reads Circle Track magazine, but they've run a very good series of articles on suspension analysis based on the moment center concept. The moment center is the geometric point that the car suspension rolls around. It is different for each end of the car, of course, since the suspensions are different. The distance between the moment center and the center of gravity for that end of the car is the moment arm that the car's weight is using to push on the suspension. The complexity here is that the moment center often varies with suspension movement, which means the moment arm length changes, which means your handling can change dramatically with suspension movement. Understanding that situation is the recent advancement that moment center analysis has brought to many forms of racing in the last few years. There are several touring lecturers in vehicle dynamics for racing cars. This is the analysis method I believe they are using in those seminars.

What all this means is that the car has two types of roll stiffness: a constant stiffness created by the springs and anti-roll bars, and a suspension geometry created stiffness based on the moment center moment arm length, which can vary. You can't really predict what a car will do unless you know both parts.

That's a summary of my limited understanding. Some day I hope to get around to figuring out the 914 suspension geometry so that I can try putting it to use. I throw it out here just to pique other's curiousity. Maybe someone else will pick up the ball and run with I further than I've been able to.

Andrew
914forme
Thanks Andrew, I now see that ^ (shift 6) Doah!

What intrigues me the most is how this post progressed from my simple calculation to see where the I should cut a sway bar arm, became a huge discussion of suspension and frame dynamics, theories, and general idiosyncrasies of the 914. And how I plan things way to much.

Take care, Stephen
914forme
Here is the formula to calculate the bar Rates!
=SUM(500000*(D19*D19*D19*D19))/((0.4244*(A19*A19)*B19)+(0.2264*(C19*C19*C19)))

This is the cleaned up version biggrin.gif

=SUM(500000*(D19^4))/((0.4244*(A19^2)*B19)+(0.2264*(C19^3)))


Borderline
914forme: the rear bar does have an 11" arm, however it acts directly (well almost directly) on the rear wheel. The front AR bar acts on the lower control arm, about 7" from the pivot point. My analysis shows the rear bar to have about 70% the stiffnes as the stock front bar. My analysis is based on how much force it takes to move the wheel 1". The stock 16mm front AR bar takes about 117# to move the front wheel 1" when the body rolls. The stock rear AR bar takes about 80#. this analysis treats the AR bar like a torsion bar half as long as the AR bar. If you assume that the AR bar link on the inside drops the same amount as the link on the outside rises, the centerline of the bar doesn't twist at all.

Sorry: didn't mean to hijack your thread. Always looking for other viewpoints on suspension stuff and trying to learn more!

Andrew: That "moment center" sounds a lot like the "roll center" That I've read a lot about over the years.
Trekkor
I've had good results with my Smart 31mm bar.


KT
KenH
Do not forget to take in to account the the angle of the drop-link as it is moved along the attachment arm.

Ken
Downunderman
1.25" bar adjusted 4.00' out = 4,216 lbs per inch. I suggest you make up some custom hardwood springs for the rear. That probably exceeds the torsional strength of the chassis. Maybe you need a welded in cage.

I'm with JP on softish spring/stiffish AR bar. But I don't do autocross and it looks like a very different discipline to most other forms of motorsport when it comes to setup. I have found F 19mm TB and 20mm AR bar and R 180 and 19mm AR bar to be a fairly good compromise for street/track/rally. Just screw the bars up when you want to go fast.
914forme
Howard the number you quote was in inch pounds, not foot puounds! I might need a cage, I don't want to take the hit on weight. But then again, I could loose else where playing with the rules a little. Since I can go 100 pounds less than the Factory specified weight for my chassis, and take 0 points.

A Engmann Log kit will be mine soon also, install this winter, can only help. And I have a few other tricks up my sleeve also.

Do you run slicks or are you just an oversteer maniac? That rear bar is huge compariad to mine, and the front is less than my current setup? Flares and big slicks what gives?????
J P Stein
QUOTE(914forme @ Aug 25 2006, 01:41 PM) *


Do you run slicks or are you just an oversteer maniac? That rear bar is huge compariad to mine, and the front is less than my current setup? Flares and big slicks what gives?????


Howard runs road rallies in ....the far SW....way far.
These are rally (really) road races like World Rally.....the guy with the fast time wins.
Near as I can figure, Howard does what he needs to do to his suspenders so's
he go faster than the other guy over the open road.....no small feat considering the trees & other shittage lining these roads. Some of his alignment specs are much wierder than anything that comes from AX.

He wrote once that he runs 3 deg caster.
One assumes that is to negate some of the self centering features of the 6 deg that AXers run. You really don't wanna hear how the self centering of the front suspension can be used to an advantage in dire AX conditions biggrin.gif

Yes, these threads tend to wander thru the subject matter when suspension work comes up. Those of us that pay attention to this stuff can learn all kinds of interesting crap....useful or not. laugh.gif

Brad Roberts
Easily one of the best threads I have ever seen posted on this site clap56.gif

QUOTE
If you think Brad is the greatest AXer to come down the pike, go with his thinking.


I'm the first to admit that I suck at AutoX'ing. I can get a car around the track, but I feel the two damn near share nothing in common when it comes to setup (for serious AutoX cars)

One of the main reasons I subscribe to the soft spring theory: I can only get 26mm Tbars into a 914 control arm. Not everyone is running coil overs. Also: I cannot buy springs in 5 or 10lb increments. It requires me to run tender springs and most PCA/POC classes for 914's dont allow tenders.

Ask me about the setup on a Boxster or GT3 and it changes to higher spring rates and smaller bars.

Damn. This is a REALLY good thread.


B
DNHunt
I really wish I hadn't read this. After 3 years of reading posts and learning I've gotten to the point i can take care of most of the day to day things and repair stuff I bust. Now I realize there isa whole world of mystery I need to look into. Damn you guys!

Dave
Brad Roberts
Dave,

dont take this stuff too seriously. It is not like we are dealing with a new car that has NO devlopment. I promise I can give you a setup that your can drive.

I have found this with pro's: they can drive the wheels off of anything you put them in as long as the setup is SAFE. You can throw all the engineering at it you want.. it still comes down to what the driver is most comfortable with. I know where this starting point is for most narrow body 914's on 205 sticky tires.

Sometimes people spend too much time worrying about the setup when they should be getting seat time on a "marginal" setup.

Trying to teach someone to communicate what the car is doing, I find, is more difficult than the actual setup changes needed to correct something. Is it oversteering or understeering at corner entry? Is the car neutral at the apex? Is it oversteering or understeering at corner exit? Is it power on understeering or oversteering in XX corner? Once you understand the questions.. making the changes becomes easy.


B
TravisNeff
You could do the figuring the easy way - check the Smart Racing catalog, they have spring rate ranges (for adjustable bars) for their big anti-sway bars.
J P Stein
What Brad says is true. There are times when stuff happens ....the tires go off, the course doesn't suit your car, the moon is full...yada. These are the times when you need to do the best driving you can to over come your real or percieved problems.
It's the time to practice making the car rotate when it doesn't want to. Braking way late into a Chicago box and still making it thru and other such stuff. If you loose it, you've learned something, eh?

Tho I have never driven Dave's car, I have ridden along with his son at the wheel.
Decent handling & power....enuff poop to kick the back end out as required....a good street/AX combo. No glaring faults at the speeds he was going.

The boy hadn't (at the time) gotten to the full time controlled ragged edge needed to take a step up to the fastest of the 205 bunch. That's where the faults are found....both in the car and in ones driving.....trust me on this....Mr Kotzian again demonstrated the difference between the ragged edge as I do it and a controlled ragged edge as he does it....it's about a second & a half biggrin.gif
Borderline
Good to have the non-club back up and running! I did the AX at Marina last Sat. I'm still very slow but had a great time. Adding the rear sway bar and going a little stiffer on the rear springs made all the difference in handling. I'm still trying to figure out what it was doing!!! It seemed to turn in pretty well at corner entry and a little oversteer at corner exit. It would call it power oversteer, but I don't have any power to induce it. It really didn't like throttle off in the middle of a corner. I've really got to learn to keep my foot in it and not back off when things get a little lose. It was a little tail happy in the chicane so I stiffened the front shocks some. It was pretty well behaved after that. I think I'm going to leave it alone for the next couple events and see if I can improve my driving. I love to tinker with settings and its going to be hard just to leave it alone.

This is a great thread. I always thought that changing the sway bar diameter was a very large change in stiffness and that adjusting the arm radius was minor tuning. But, by adjusting my 19mm bar in about 1.5", it can be the equivalent of a 22mm bar! I love this stuff! boldblue.gif
914forme
QUOTE(Borderline @ Sep 1 2006, 11:26 PM) *

This is a great thread. I always thought that changing the sway bar diameter was a very large change in stiffness and that adjusting the arm radius was minor tuning. But, by adjusting my 19mm bar in about 1.5", it can be the equivalent of a 22mm bar! I love this stuff!


Glad to hear you got it balanced or at least closer to balance for your setup/driver. In reality, I can make my new 31mm bar as soft as a stock 15mm, or as hard as I can possibly imagine. I have a felling once I get the front bar setup, I might be looking to do the same with the rear bar. Adjustable rears would make it oh so much easier for me to screw up my cars handling even more. biggrin.gif

Take care, Stephen
John
I like this thread. It's the same thing I went through 15-16 years ago when trying to set up the track car. While reading what the car was doing, we felt the need to get heavier springs and sway bars.

I did the same (or at least very similar) sway bar spring rate calculations, as well as the torsion bar spring rates and came up with a setup that was well balanced and took a minimum of tweaking the front sway bar to make for a very neutral handling car that we still push very hard on the track today.

The comments made about seat time and getting to know what the car is telling you is one of the most important steps in "dialing in" the suspension. Without that feedback, you can throw a ton of money into swapping out parts for little or no benefit.

One thing to really keep in mind when going to these MEGA front swaybars is that the swaybar is still transmitting it's force to the body through some relatively thin sheet metal. The inner wheel well can bend and begin to tear with even a small bar if the arms are made short enough. The metal in those areas should be well reinforced (and not just with the backing plate). I have seen the mounts tear out the same size as the backing plate.

just some food for thought.
914forme
John, all that is good info I have taken the swaybar backing into consideration from day one with this chassis. but I was using a much smaller bar. So for the new king of sway bars I am taking notes from Nascar boys and building a new setup, different from most if not all 914s out there.

One realization I am making is as I get closer to the ragged edge of auto-x, my car is becoming much less of a street car. I am considering taking it off the street, and towing it to events now. If I do that spring rates can go way up. I do so enjoy driving the car though it is usually only to and from events.

So here are the details of the new mounts, and systems. I am basing my design off the fact I will be using 1.25" end sway bar. I am installing a central tub, into the car, 1.75" ID tub, from side to side, approx. 34.5" long. The sway bars are 37.5" long, the arms are about 1" thick. So that gets me down to 1" of play for bushing collar, and swaybar collar. These will be bolted together at first to finish mock up. Then it will all be welded.

Outside I will add a 16 gauge plate from dimple down spreading out as I go down to rack area. Inside I will be adding a larger plate that goes front to rear, and bends to tie into the front trunk wall. I will also add a box section to tie the support tube and the lowest corner diagonally. It adds a third dimension to the shear points and strength the entire assembly. This assembly should not see any side loading except from the resistance of the bar trying to play in the bushings. This will be taken up by the collars on each end.

Added some simple sketches of the design. Advantages , I can now swap bars all day long. Since the bushings are the same, if I have too much front bar, I can go down a size, or go up. Until I hit the inner tube wall, with clearance.

Again just goes to show, I over think this stuff. biggrin.gif
groot
Hmmmm.... kind of like this?

I don't think your support tube is required..... If you use rod ends on your end links you shouldn't have side loads on your bar....so all of the load into the stabilizer bar should be shear to the mounting plane.....
914forme
See I over think things.

Kevin,

Where did you get that bearing? And then see I am never a pioneer, that is what is so wonderful about this non-club. Somebody has already invented the wheel 3x over.

Take care, Stephen
914forme
Okay on a side note JP was asking if I knew corner weights etc...

The answer is yes, I do know my corner weights. But What I was trying yesterday was to figure out true spring rates as they applied to the tire contact patch.

So out came the jack, a scale, a set of chains, and the dreaded jack stands. I needed to fix an oil cooler leak anyway.

So I put it up on jacks, chained the chassis down to the floor. Placed the scale onto of my jack, with a backer plate. Jacked up just under the tire. My scale only goes to 300 pounds, it is a shippers Digital scale. So I would jack it up, get contact on the tire, I got my tape out and measured a location on the wheel as reference. Zero out the scale, and jack up 1 inch. Took note of the readings, and repeated this 5 times. Added the numbers together and averaged them out.

Now this was with out sway bars added I disconnected each one of them.
Front side I had 196.5 lbs and 193.3 lbs. Rears I had 215.1 lbs, and 217.3 lbs. I am confused by the numbers. Is this the true number via spring rate or does this also include unsprung weight. I was expecting the rates to be less than the calculated rate of the springs. Due to real world variations, I was not expecting it to be more.

So possibilities I see right off the bat with this method.
1. it also took into account my wheel and tire weight plus part of my suspension arms and shocks.

2. the Gas Bilstiens add to the rate.
Borderline
Kevin: What am I seeing in that photo? You've obviously got coil-overs and have replaced the lower arm with rods. Is the lower end of the AR bar link attached to one of the rods? You must have used Andy's camera poke.gif You've got a very wide range of adjustment. How many of those holes in the arm have you used?
groot
Sorry, I don't remember where I got that bearing.... it was 2 years ago and I ordered it from some industrial bearing supplier off of the web.... It's a pretty cool piece, it has two stamped pieces that allow the bearing to pivot and the bearing is a ball bearing unit that fits around the 1" stablizer bar end and uses set screws to hold it. I'm a big fan of using ball bearings on a stabizer bar, one more way to reduce stiction. McMaster Carr has stuff similar, but not exactly what I wanted. Bar and arms are from Speedway Engineering.

I had the bar set where you see it, but with the new front end I've stiffened the bar 2 more holes this weekend. Still oversteers after about 6 laps. Still working on that problem.

The rods are there because I moved my inner pivot points for better geometry and incorporated a double adjustable strut insert. There are details in my blog and in older threads on the subject.
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