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Automotive Powered Off Road (AKA: Buggys, Jeeps, Trucks, Etc,Etc. ) => Chassis and Suspension => Topic started by: fabr on May 14, 2012, 07:05:36 PM

Title: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 14, 2012, 07:05:36 PM
Out of the box, just copying R/C stuff, won't crossover to full size, no need, would/would not work,stupid to try,hasn't been done for a reason or just another step in the evolution of long travel offroad suspensions? Take a look at the pics and see if there's some reason it would (or not) not crossover to a full size 2500-2800 pound desert car.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Nutz4sand on May 14, 2012, 07:54:13 PM
I am big into rc and have had those very sway bars.

They do not counteract but actually make it worse.  Follow the motion path.

In a normal sway bar the one side goes up and puts the same upward pull on the other side. Leveling the vehicle (or trying to anyways)

These push up on one side and push DOWN on the other.  Making it lean worse.

Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Carlriddle on May 15, 2012, 05:21:24 AM
Unless there's some positive stop that would keep lever arm from pushing down I'm with Nutz,  ;D  Some of the offroad racing trucks run sway bars, but for 95% of us, no need.  But that 5% is the reason we do 95% of this stuff.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 15, 2012, 05:58:53 AM
I don't agree that we don't need sway bars. I'm also not sure that we are looking at this particular setup correctly either. At first glance I agree with you guys but with it here in front of me and cycling it through a lot of different scenarios I'm not so convinced it doesn't function pretty well. Not in a traditional sense but perhaps more  suited to the long suspension travels we use. Honestly I can't see how a traditional sway bar can work effectively giving both independent wheel action AND minimizing sway/body roll. Pretty hard to do both well at the same time with a traditional bar IMO.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Lance-W on May 15, 2012, 08:01:49 AM
Those tiny little bars connecting the horizontal shock to the A-arm WILL bend when they're put in compression.  They'd have to be big hollow tubes to take the load generated when the arm pushes up.  Might work on that model that weighs a few pounds but scale it up and they'd get huge.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 15, 2012, 08:24:10 AM
Maybe ,maybe not. The spring pressures would not be extreme ,actually pretty light,to resist body roll. I agree that the "pushrods" would need to be hollow and of sufficient diameter to not bend/deflect. Doable , IMO. I mean I run upwards of 800# spring pressure on my race engines valve springs@.800 lift. 7/16" rods do a fine job @ 8500RPM. Seems to me a 1" or so hollow rod would be more than capable.
  I'm just screwing around ,thinking,looking at lots of things. Some work ,some don't. Never hurts to keep an open mind. Remember when they said long travel wasn't needed?
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: vidio1 on May 15, 2012, 09:53:46 AM
It would have to be a 50/50 shock or else it would be biased to one side. That might be an advantage for one of those left turn cars........

Honestly with it "floating" I don't see how it's any more effective than a traditional ASB at keeping a car flat. I can see where it would be better at keeping the wheels planted thou.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 15, 2012, 11:15:36 AM
It would have to be a 50/50 shock or else it would be biased to one side. That might be an advantage for one of those left turn cars........

Honestly with it "floating" I don't see how it's any more effective than a traditional ASB at keeping a car flat. I can see where it would be better at keeping the wheels planted thou.
+1 maybe. I don't think the purpose ever was to function as a traditional sway bar.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Nutz4sand on May 15, 2012, 11:22:44 AM
Those same systems on the rc cars were made for "extreme jumping" as they helped prevent bottoming out was the claim.

Some of them on certain models were so poorly designed they restricted the trucks stock suspension movement quite badely. The manuafacture was asked about this and stated. "Most rc trucks don't use all thier travel anyways." Total douche answer to me.

Most rc guys I know air these things out so high they show up on local airport radars. Bottoming out is mandatory for most to have "fun" in rc!

The makers of this suspension setup came one night and left the next. The only reason I had one is it came on a truck I got a good deal on on ebay.

With clean parts they were later considered a show option for shelf queens.

I still do not see a setup just like this really helping the leaning. It just makes the suspension a little stiffer and there are better ways to skin that cat IMO. 


Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 15, 2012, 01:14:36 PM
Those same systems on the rc cars were made for "extreme jumping" as they helped prevent bottoming out was the claim.

Some of them on certain models were so poorly designed they restricted the trucks stock suspension movement quite badely. The manuafacture was asked about this and stated. "Most rc trucks don't use all thier travel anyways." Total douche answer to me.

Most rc guys I know air these things out so high they show up on local airport radars. Bottoming out is mandatory for most to have "fun" in rc!

The makers of this suspension setup came one night and left the next. The only reason I had one is it came on a truck I got a good deal on on ebay.

With clean parts they were later considered a show option for shelf queens.

I still do not see a setup just like this really helping the leaning. It just makes the suspension a little stiffer and there are better ways to skin that cat IMO.
Probably quite right . Still there's something that intrigues me about this. I agree fully that with the shock floating between the 2 fulcrums that it will actually aggravate body roll. If there were 2 shocks fixed at one end it would be no different than a rocker arm suspension. Again ,no benefit so far as body roll is concerned. In the end,no net benefit and with the added weight,complexity and expense. Still intrigued though.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandycrack on May 15, 2012, 05:46:53 PM
I know my buggy is bigger and heavier and I am putting a sway bar on it. I got my setup from Speedway engineering.  It is a traditional setup.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 15, 2012, 07:41:34 PM
Same here. Gonna get a bar no doubt. In the sand it's not noticable much but on hardpack or pavement...............................well,let's just say it could be improved.The sudden over steer under hard cornering is a bit unnerving. 
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandracer1 on May 17, 2012, 04:46:01 AM
My bar pushed the bushing out of the frame tube this week while at L/S and turning ability went to shit. Unnerving body roll and loss of turning speed. It sucked. Mine is a trditional style with the torsion bar running through the frame under the seat. I can back my car in on the pavement and be drifting on the way out. They make a huge difference.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 17, 2012, 06:11:17 AM
Ya,no doubt,IMO all cars need one.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: trans man on May 17, 2012, 06:12:57 PM
I could see running a sway bar, but ONLY on the rear suspension. 8) 8) 8)
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 17, 2012, 07:43:58 PM
Why? Guys with them front and rear seem to like them. I see no negatives.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on May 17, 2012, 10:52:17 PM
Probably quite right . Still there's something that intrigues me about this. I agree fully that with the shock floating between the 2 fulcrums that it will actually aggravate body roll. If there were 2 shocks fixed at one end it would be no different than a rocker arm suspension. Again ,no benefit so far as body roll is concerned. In the end,no net benefit and with the added weight,complexity and expense. Still intrigued though.

I think Y'all missed the point of how this works.  ;D

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If you look at the linkage that is connected to each end of the top shock you will notice that it isn't real symetrical.   If both arms are cycled at the same time then there will be exactly equal pressure to the linkage on each side.  However if one side is compressed, the linkage ratio is such that the side compressed more will have a longer distance from the linkage pivot to the shock pivot than the opposite side, resulting in more down pressure from the shock going to the side compressed further.  This will have an anti sway affect.

IMO it won't be greatly noticeable or affective, however in theory it could produce some sway resistance.

ETA:  Just to clarify, if the left side stayed in the same position but you compressed the right side till the right linkage pivot and the right end of the shock where it mounts to the pivot were in line vertically, the leverage distance on the right side would be about double that on the left side.  Therefore whatever pressure the spring was producing would be resulting in double the pressure down on the right side than the left.

I am not taking into account the leverage difference from the linkage down to the Arm, so it probably gets messier.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 18, 2012, 05:58:08 AM
That is what I saw also but I also ,as you said ,see it as giving a only very small anti roll benefit. So small that on a small scale it MIGHT help but when scaled up full size would likely not work the same. At any rate it is more complicated with negligible possible benefits over a conventional bar.Another thing a person would notice is the importance of zero play in all the pivots. To do that would IMO,make for a heavier setup than a simple bar arrangement.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 18, 2012, 06:04:39 AM
We should remember that the function a sway bar provides is to actually LIFT the inside tire/suspension when the outside tire/suspension compresses to pull the inside down,in effect adding weight to the inside tire /suspension,lessening body roll. In that respect a bar does the job better than the transverse shock and linkage would. Still,on a long travel,there is something that makes me rethink this principle compared to a bar over and over. I like the principle but don't see a net benefit. Oh,well,I like people that are not afraid to try new things whether on RC stuff or full size.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Carlriddle on May 18, 2012, 06:30:04 AM
We should remember that the function a sway bar provides is to actually LIFT the inside tire/suspension when the outside tire/suspension compresses to pull the inside down,in effect adding weight to the inside tire /suspension,lessening body roll. In that respect a bar does the job better than the transverse shock and linkage would. Still,on a long travel,there is something that makes me rethink this principle compared to a bar over and over. I like the principle but don't see a net benefit. Oh,well,I like people that are not afraid to try new things whether on RC stuff or full size.

That was my thinking, when outside tire compresses, inside tire should compress too.  That setup should help some, but is still going to push down inside tire.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandracer1 on May 18, 2012, 12:49:13 PM
I lost my swaybar this trip on the second day. IT SUCKED!!!!!! Sucker would not turn, body roll like crazy. It took twice the steering input to turn the little beast. Mine is only on the rear and without it the inside front tire will hike up about 6" to 1' off the ground. WITH it I can slide it into turns on pavement and be drifting with knobbies on the way out of the turn. It sure keeps my car planted to the ground. I really do not notice a big difference through woops and stuff. The little change it makes there is well worth the improvements everywhere else. I suggest one for everyone. Mine is a sprintcarkind of set up.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandycrack on May 18, 2012, 01:02:04 PM
To me I think the old addage of "keep it simple" might be the best approach.  A conventional bar is proven and very effective.  I have seen several LT cars out at the SSSS with new ideas like this and while they look cool you never see the new approach take off and flood the market.  I suspect it is related to higher cost to build and maintain and no markable improvement to the conventional bar. 

As for front and rear bars I am with Faber.  I am not doing this to my car, but the guys I have talked to seem to like it alot.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 18, 2012, 01:10:43 PM
I agree,at least for now,KISS is the way to go. But I like to at least think I keep an open mind. Not sure what I will do but if I drive this thing on hard pack much more it will at least get a rear bar and likely  front also. I'm toying with doing a bar disconnect also.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandycrack on May 21, 2012, 08:58:55 AM
I think one should always be looking for new technology and best practice or you might miss some favorable improvements.

I made my bar where the arms could be removed very easily, but I dont see me doing that much.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on May 21, 2012, 09:57:32 AM
 I've seen 4WD front manual hubs used as disconnects. 2 seconds to engage/disengage.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Monster_44 on August 08, 2012, 09:23:51 PM
I have a link for the sway bar kits used on trophy trucks and short course trucks.  The only thing is they are straight axle and I'm assuming you want to do a arm rear?  Click link, go to products, go down to suspension kit, the sway bars are in that section.  Camburg makes all kinds of really neat and expensive shit!

http://www.camburg.com/ (http://www.camburg.com/)
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Monster_44 on August 08, 2012, 09:48:55 PM
Check this page out too.  He's using a sway bar on a rear a arm buggy.

http://www.minibuggy.net/forum/suspension-wheels-tires/13415-rear-sway-bar-needed-mini-buggy-please-help-design.html (http://www.minibuggy.net/forum/suspension-wheels-tires/13415-rear-sway-bar-needed-mini-buggy-please-help-design.html)
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: dsrace on August 09, 2012, 10:47:01 AM
I have had the chance to talk with several people now that run v-8 4 to 2 seaters mid and rear. they have all had the same thing to say and that is the sway bars are a must have. now having said that there is more to consider, on a few of those rails the owner have broke those sway bars and had to run w/o them. in 1 case in particular the v-8 mid engine 2 seater wound up pulling the front one off because he said it didn't handle right with the rear missing. when he got the new one in for the rear he installed it but left the front off and pre-ferred that set up more than with both on. now one of the 4 seat rear guys aslo pulled his front off and pre-ferred it that way also. another guy I talked to loosed the adjustments on the front and pre-ferred that as well. now you have to also consider these rails are 95% sand only but something to think about.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on August 09, 2012, 12:31:32 PM
I believe there would be a definite different setup for dunes vs hardpack.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: ironknot on August 16, 2012, 09:40:16 PM
Old Dodges used to run torsion bar spring along the chassis rails and use the lower arm as a connection, just to give you an idea of wear I'm coming from. I've seen two torsion bars connected with a gear on each at one end and an arm on the other with the arm connected to the lower suspension. This works like a traditional sway bar. The two halves of the sway bar can be placed together this would centralise the weight and maybe with an alloy link work well with an A-arm front-end. . . Out of the box
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on August 17, 2012, 05:54:01 AM
I think I follow that.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: LiveWire on August 17, 2012, 11:49:08 AM
I think this is an example of what he is saying...

Compared to the suspension you posted pictures of, the side to side shock would be a hard link. The pivot arms would be connected to the suspension arms with torsion bars. The idea being is packaging caused you you to mount a traditional sway bar high, you could relocate the weight lower and/or closer to the center of the machine. I take the gears to mean using something like a rack and pinion on each side instead of a bell crank style arm.

In order to work like a traditional sway bar and not the opposite like that RC car setup, the rack would have to be over one torsion bar and under the other side. So left arm moves up twisting left torsion bar in clockwise direction, pushes rack above gear to right which twists right torsion bar in counter clockwise direction since rack is below which in turn reduces spring load on the right side.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on August 17, 2012, 01:07:46 PM
Clear as mud! I see what you mean tho. THanks guys.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 17, 2013, 07:24:20 PM
seems to be based on the third spring idea that a lot of aero cars run  and formula vees  it increase the ride rate but not the roll rate ,but its not a sway bar at all
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 17, 2013, 08:26:46 PM
Educate me more please.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: sandycrack on January 18, 2013, 07:02:42 AM
Please do post more info and bigger pics would be nice also.  These damn old eyes just cant see like they used to.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 18, 2013, 01:59:11 PM
I'm not really sure what you what to know?
sway bars increase the roll resistance or roll rate they have no effect on the ride rate the way that set up is it may even decrease roll resistance ,maybe who ever designed this wanted to do that or may be he or she thought it looked good


there is one main difference between black track and off road cars and its where we get traction from ,black track its in the surface and the cars use whats available,  off road the tyres create traction using cutting edges ( any thing that stick out off you wheel) and vertical load
This is the main reason you don't see as many sway bars in off road we genrally want the ride rate to be close to the roll rate as  we need weight transfer 

At the end of the day it comes down to the rubber on the road and every thing we do is to make it stick better

but as usual nothings ever that simple if you want more info on how they use the third spring on the black stuff ill have to do a sketch as theres not to many good pics out there (they don't like people getting close ups lol)
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 18, 2013, 04:28:24 PM
I'm not really sure what you what to know?
sway bars increase the roll resistance or roll rate they have no effect on the ride rate the way that set up is it may even decrease roll resistance ,maybe who ever designed this wanted to do that or may be he or she thought it looked good


there is one main difference between black track and off road cars and its where we get traction from ,black track its in the surface and the cars use whats available,  off road the tyres create traction using cutting edges ( any thing that stick out off you wheel) and vertical load
This is the main reason you don't see as many sway bars in off road we genrally want the ride rate to be close to the roll rate as  we need weight transfer 

At the end of the day it comes down to the rubber on the road and every thing we do is to make it stick better

but as usual nothings ever that simple if you want more info on how they use the third spring on the black stuff ill have to do a sketch as theres not to many good pics out there (they don't like people getting close ups lol)


That's what I would like to know more about. The rest I know .
My reasoning for a sway bar is,IMO,more simplistic.Minimizing body roll. Nothing else. BUT,it seems like a arm cars don't roll nearly as much as trailing arm cars. Can anyone help me understand why that is?
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 18, 2013, 05:37:47 PM
more than likely roll centre to cg height
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 18, 2013, 09:47:58 PM
I never investigated it but I would not have thought that an a arm car inherently would have a higher roll center than a trailing arm car would.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: BDKW1 on January 18, 2013, 10:21:24 PM
seems to be based on the third spring idea that a lot of aero cars run  and formula vees  it increase the ride rate but not the roll rate ,but its not a sway bar at all

Yup, that extra shock on the RC car will do absolutely nothing for roll control. Extra spring rate yes.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 18, 2013, 10:31:18 PM
yes it may be ,well it would have to be lower to create more roll
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 19, 2013, 06:35:19 AM
SO ,what,it functions as an adjustable ,additional spring rate?
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 19, 2013, 02:39:56 PM
its more like a lever the bigger distance between the two ,centre of gravity height and roll centre the bigger the lever ,and yes it is adjustable .ride heights the easy way , geometry ,its also a balance thing front to rear
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 20, 2013, 10:09:51 PM

Yup, that extra shock on the RC car will do absolutely nothing for roll control. Extra spring rate yes.

I don't agree.  If you look at the way the linkages are setup, when the vehicle rolls, because of the linkage throws, the third spring will apply more force down on the compressed side than the uncompressed side.

If the vehicle goes straight down then it applies pressure to both sides equally.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 20, 2013, 10:24:50 PM
So here is an outline of the linkage points.  Pardon the paint skills.

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Now if we compress only the right side and move the linkage to this position, the top spring will increase the pressure on both sides, but the pressure on the right side will be more than the pressure on the left side because of the mechanical advantage.  (The right side is 90 degrees to the lever while the left is still around 45 degrees.)

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Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 20, 2013, 11:26:06 PM
two things two remember the real name for a sway bar is an anti swaybar and this is all acting against that big lump of steel aluminium fuel oil and meat in the middle (granted not so much on an rc car) .It will still increase the spring rate on the other side and make more body roll, remember we are going around a corner ,it not just the wheel in bump as this is ride rate not roll rate and it will increase the ride rate just as you have explained
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 21, 2013, 07:09:10 PM
two things two remember the real name for a sway bar is an anti swaybar and this is all acting against that big lump of steel aluminium fuel oil and meat in the middle (granted not so much on an rc car) .It will still increase the spring rate on the other side and make more body roll, remember we are going around a corner ,it not just the wheel in bump as this is ride rate not roll rate and it will increase the ride rate just as you have explained  

More?  Surely you mean less.  It increases the spring rate on both sides but more on the depressed side.

So if the ride rate increases on the depressed side then that will create less body roll.  Or have an anti sway affect.



Fingers crossed...  Someone sees how it works.  ;D
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: BDKW1 on January 21, 2013, 07:14:50 PM
Now if we compress only the right side and move the linkage to this position, the top spring will increase the pressure on both sides, but the pressure on the right side will be more than the pressure on the left side because of the mechanical advantage.  (The right side is 90 degrees to the lever while the left is still around 45 degrees.)

What your describing would be a spring rate increase for a one sided suspension load. This I can see. Body roll from lateral cornering forces would be moving both bell crank pivots equally. There may be some resistance due to the mechanical progression curves but I doubt it would do much. I would have to draw that one up to see for sure. The upside that I can see is that it would be a dampened spring unlike a normal sway bar that screws up your spring rate.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 21, 2013, 08:23:08 PM
Now you guys are talking about what I thought at the beginning ,I think.....................
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 21, 2013, 09:41:21 PM

What your describing would be a spring rate increase for a one sided suspension load. This I can see. Body roll from lateral cornering forces would be moving both bell crank pivots equally. There may be some resistance due to the mechanical progression curves but I doubt it would do much. I would have to draw that one up to see for sure. The upside that I can see is that it would be a dampened spring unlike a normal sway bar that screws up your spring rate.

I agree 100%

It would be moving them equally, but the one being compressed would be getting more leverage while the one being uncompressed would be getting less leverage.  Basically increasing the spring rate on the compressed side and reducing it on the uncompressed side.   That is why the shape and geometry of those bell cranks are so important.

I agree that it would have very little affect, a few percentage points change in spring rate from one side to the other.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 21, 2013, 09:45:33 PM
Now you guys are talking about what I thought at the beginning ,I think.....................

I think so.

Last picture, just like the shock to A-arm discussion the closer you are to 90 degrees, the more resistance your spring and shock will develop.  So assuming the right side is compressed and the linkage was as shown in red below, the shock/spring will be pushing with the same pressure on both sides, but the right side is at 90 degrees, therefore putting maximum torque into the right linkage noted #2.  While the left side is at 45degrees to the linkage pivot and putting less torque into the left linkage noted #1.

You can also look at the distance from the blue line representing the shock center line down to the linkage pivot.  At #1 the distance is shorter thus it has less leverage, while at #2 the distance is greater thus it has more leverage.

In the scheme of things it isn't a very large difference but it will have some affect.

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Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 21, 2013, 09:54:43 PM
ill put it another way the porsha LMP2 car in the pic i posted its the same set up just packaged diferent so why do they still run a sway bar?
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: Engineer on January 21, 2013, 10:15:26 PM
ill put it another way the porsha LMP2 car in the pic i posted its the same set up just packaged diferent so why do they still run a sway bar?

Probably tuneability.  I think BDKW1 pointed it out that the shock would provide damping to the anti sway.  The linkage ratios do not allow for any adjustability to the anti sway affects so the anti sway bar could be used to add or reduce the total anti sway resistance or to add preload to one side or the other.  I notice that there are still shocks on both sides so that total damping could be adjusted for each side independently and would function independently.  The only spring on the car is on the center shock so based on the linkage it would provide some anti sway, but the few percentage change probably isn't enough to eliminate the need for a sway bar.  The small amount of wheel travel on that car is going to make the effects even less.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: fabr on January 22, 2013, 06:02:57 AM
Personally,I feel that the small amount of change is exactly what they are looking for given that the suspension it is used on has very little travel . IMO,that is the very fine adjustment they are looking for. WE ,on the other hand ,with long travel would likely see little to no benefit from such minute adjustments considering the infinite terrain we run on.
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 22, 2013, 08:15:35 AM
the main reason they use them is on high speed tracks with long straights aero load can get so high it will push the car into the track(aero cars are sencitive to ride hight changes) but if they increase the main spring rate or preload the car would be less compliant a round corners on lower speed tracks they some times remove the spring (as with all race cars we try to run the softest springs we can)

the second reason is under acceleration it tends to load both rear tries more evenly ,genrally they are only on the rear of the car
Title: Re: Sway Bar-Thinking Out of the Box?
Post by: gap351 on January 22, 2013, 08:24:20 AM
Probably tuneability.  I think BDKW1 pointed it out that the shock would provide damping to the anti sway.  The linkage ratios do not allow for any adjustability to the anti sway affects so the anti sway bar could be used to add or reduce the total anti sway resistance or to add preload to one side or the other.  I notice that there are still shocks on both sides so that total damping could be adjusted for each side independently and would function independently.  The only spring on the car is on the center shock so based on the linkage it would provide some anti sway, but the few percentage change probably isn't enough to eliminate the need for a sway bar.  The small amount of wheel travel on that car is going to make the effects even less.

there are two torshon bars as well
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