PDA

View Full Version : Understanding the function of a sway bar?



Dr. Design
02-18-2004, 03:09 PM
Hello All,
We at D3 have noticed that there are companies out there that claim that sway bars stiffen the chassis rather then using chassis braces. In reality the two are very different. Most people think that by adding an aftermarket sway bay it will stiffen the chassis. Wrong! The following is kind of an extreme example but you will get the basic idea. The sway bar will reduce the body from rolling on the frame and suspension. Picture the car from the rear. Pretend that there is a ball between the suspension and the body that allows for the body to pivot off of the ball. What the sway bar will do is reduce the amount of pivot that the body has on that ball. The sway bar does exactly what it is supposed to do. One thing it will not do is stiffen the chassis. ONLY chassis stiffeners will do that. So what we have here is the chassis secured on the suspension with body roll.
Question? What is keeping the chassis from twisting? A sway bar, springs, and shocks are not the answer to superior handling. Even if you use stiffer springs, stronger shocks, or a huge sway bar, what is keeping the corners of the car from moving at different levels (aka twisting)? When the chassis twists, it wastes energy and takes away performance from your suspension. If anything it is even more apparent that the car is twisting. If you add a chassis kit or a roll cage to the car it will keep the chassis neutral and all four corners in sync with each other. As a result this will allow the suspension to do what is supposed to do. The 1st law of physics states that, "An object at rest or moving at constant velocity will continue to do so unless acted upon by an external force". Only chassis bracing can act as that external force. Please let us know if there are any questions.
Thank you,

Low Rider
02-18-2004, 03:49 PM
Not to be a prick but, since you brought it up: that is Newton's first law of motion not the first law of physics. On top of that, since when did a little bit of chasis flex become a bad thing. Ask any Honda mechanic: the EP3 chasis is built like a rock. 90% of the drivers on this planet will never drive their cars hard enough to notice the benefits of some cheezy x-brace. In my opinion, there are way better things to spend your money on and improvements to your suspension are far more noticable than the addition of an x-brace.

tony speed
02-18-2004, 04:08 PM
Originally posted by Low Rider
Not to be a prick but, since you brought it up: that is Newton's first law of motion not the first law of physics. On top of that, since when did a little bit of chasis flex become a bad thing. Ask any Honda mechanic: the EP3 chasis is built like a rock. 90% of the drivers on this planet will never drive their cars hard enough to notice the benefits of some cheezy x-brace. In my opinion, there are way better things to spend your money on and improvements to your suspension are far more noticable than the addition of an x-brace.


that depends on what you want to do with your car.

Rueda del Queso
02-18-2004, 04:22 PM
Ok, so chassis braces are good. When are you going to start selling some for the EP, aside from the double-x brace?

FCobra94
02-18-2004, 06:13 PM
Originally posted by Rueda del Queso
Ok, so chassis braces are good. When are you going to start selling some for the EP, aside from the double-x brace?

As I understand it, the double-x brace is a chassis brace...

Dr. Design
02-18-2004, 07:11 PM
Hello,
Thank you for your feedback. Chassis flex is fine....if you do not intend to drive the car with any sort of passion. If you intend to go over the recommended speed limit through a turn, then you are speaking our language. Chassis bracing, or any form of suspension modifications, can greatly benefit the EP3 application. Most aftermarket components are built on the fact that a certain percentage of owners will drive the cars more aggressively then the typical vehicle demographics. When our engineers looked at the EP3/DC5 chassis it was determined that the platform could use ALOT of bracing. When it comes to motorsports, eliminating unwanted chassis flex is KEY! Here is an example how important it is to the manufacture to eliminate chassis flex. When GM/Honda/Toyota/etc... want to increase the handling of a vehicle, they typically start by making the chassis X% more rigid. It is far more cost effective to use supplemental bracing rather then completely restructuring the chassis. Please let us know if there are any other questions.

Thank you,




Originally posted by Low Rider
Not to be a prick but, since you brought it up: that is Newton's first law of motion not the first law of physics. On top of that, since when did a little bit of chasis flex become a bad thing. Ask any Honda mechanic: the EP3 chasis is built like a rock. 90% of the drivers on this planet will never drive their cars hard enough to notice the benefits of some cheezy x-brace. In my opinion, there are way better things to spend your money on and improvements to your suspension are far more noticable than the addition of an x-brace.

FCobra94
02-18-2004, 08:19 PM
When GM/Honda/Toyota/etc... want to increase the handling of a vehicle, they typically start by making the chassis X% more rigid. It is far more cost effective to use supplemental bracing rather then completely restructuring the chassis.

Tell me about it. When Mustang owners start modding, the first thing they look at is usually sub-frame connectors. Mine has a bit of flex, even w/ upgraded shocks/springs, but I could only imagine what the convertable owners feel! I'm sure they're almost a neccessity on those cars.

Anyways, I figured since the Si felt a good bit tighter than the Mustang, it wouldn't require any extra bracing, but so far I've been hearing otherwise.

This X brace is sounding more and more appetizing to me :tongue: hehe

foilpan
02-18-2004, 08:38 PM
aside from improved handling characteristics for those seeking them, are there any negative consequences related to increased chassis stiffness over the life of the chassis?

realistically, i'd like a reasonably nimble ride without the harshness that would make everyday driving unbearable. i didn't buy an EP3 because it's a race machine; i bought it because it's an SI, an economical and quick little car.

so, what are the long term structural consequences -- if any -- of increasing chassis stiffness? or is this the wrong question because many enthusiasts plan to get rid of their EP3s in a few years anyway? i plan on driving mine for the long haul.

Dunrick
02-19-2004, 06:54 AM
any idea what class this xbrace is allowed in for scca autox?

Jpax
02-19-2004, 08:52 AM
Originally posted by Dunrick
any idea what class this xbrace is allowed in for scca autox?

ST2 numbnuts... :D


Dr Design and his team are experts in this field of chassis stiffing. I would buy this braces in a heart beat if i still had an Ep. when i had the neuspeed x brace on it was a night and day difference over stock in turning and braking.

Dunrick
02-19-2004, 09:12 AM
good to know. unfortunetly I got the neuspeed xbrace on already.

Low Rider
02-19-2004, 02:01 PM
Re:

Chassis flex is fine....if you do not intend to drive the car with any sort of passion. If you intend to go over the recommended speed limit through a turn, then you are speaking our language. Chassis bracing, or any form of suspension modifications, can greatly benefit the EP3 application.

Hmmm, that's interesting... King Motorsports has set up my suspension for me and they are of the opinion that the EP3 sub-frame is strong enough to do without an x-brace. I have also talked to Toda and Spoon about this issue and they are in agreement. I guess then that noone at these racing pedigreed factories drives with passion!:rolleyes:

Dr. Design
02-19-2004, 02:52 PM
Hello,
We are not saying they are wrong, or your setup is not a good one. We just see things a little different over here based on what our engineers have done in the past. I guess that is what happens when you have to build pro chassis from the ground up for IMSA and NHRA? It is the opinions of King Motorsports, Toda, and Spoon's that the EP3 chassis is rigid enough. This is fine. It is our opinion that any front strut tower brace MUST attach to the firewall for maximum performance gains. The point is these are just opinions. Everyone on the message boards knows that the EP3 chassis is not race ready. That is not a knock on Honda, very few factory chassis are completely race ready. Please let us know if there are any questions.
Thank you,







Originally posted by Low Rider
Hmmm, that's interesting... King Motorsports has set up my suspension for me and they are of the opinion that the EP3 sub-frame is strong enough to do without an x-brace. I have also talked to Toda and Spoon about this issue and they are in agreement. I guess then that noone at these racing pedigreed factories drives with passion!:rolleyes: [/B]

Low Rider
02-19-2004, 02:55 PM
Originally posted by Dr. Design
Hello,
We are not saying they are wrong, or your setup is not a good one. We just see things a little different over here based on what our engineers have done in the past. I guess that is what happens when you have to build pro chassis from the ground up for IMSA and NHRA? It is the opinions of King Motorsports, Toda, and Spoon's that the EP3 chassis is rigid enough. This is fine. It is our opinion that any front strut tower brace MUST attach to the firewall for maximum performance gains. The point is these are just opinions. Everyone on the message boards knows that the EP3 chassis is not race ready. That is not a knock on Honda, very few factory chassis are completely race ready. Please let us know if there are any questions.
Thank you,

I guess you are right... it would be interesting to test the car with both configurations!!!

Dr. Design
02-19-2004, 02:57 PM
You hit the nail right on the head. We would love to test our products against the others that are also well respected in the industry! Competition always makes the product better!

Thank you,



Originally posted by Low Rider
I guess you are right... it would be interesting to test the car with both configurations!!!

Zero Three Si
02-19-2004, 07:24 PM
Originally posted by PaXiE
ST2 numbnuts... :D


Dr Design and his team are experts in this field of chassis stiffing. I would buy this braces in a heart beat if i still had an Ep. when i had the neuspeed x brace on it was a night and day difference over stock in turning and braking.


I would have bought it from you nutnutz....you're gay for not selling it to me.

BTW....Dr. Design...you've really impressed me with your professionalism. The guy was pretty much calling your product out. Nice to see you stick to your guns and be polite. I'm definitly interested in getting one.

rswbrixton
02-19-2004, 07:44 PM
I have ordered the double xbrace today and am very anxious to see the difference over the Neuspeed xbrace i currently use .

Certainly the build appears second to none .

I am going to utilize the xbrace with the bracing i currently have of course . The front and rear struts (alex) , lower tie (spoon) , c-pillar (alex) and ,have also ordered inner fender braces (alex) .

On the Mugen suspension , my goal is to have this car ride like its on rails . Comfort not a huge concern . This car will quickly evolve into track/hobby car .

Looking forward to seeing other D3 Design chassis products .

jball
02-19-2004, 08:16 PM
hey dr. design,

need any more engineers? im a biomed engineer by training, but id love to learn about auto engineering. im impressed by your arguments and products, it really seems like you have your sh!t together.

tom3
02-19-2004, 09:47 PM
Originally posted by Zero Three Si
BTW....Dr. Design...you've really impressed me with your professionalism. The guy was pretty much calling your product out. Nice to see you stick to your guns and be polite. I'm definitly interested in getting one.

I agree, way to hold your composure under fire, Dr. Design. Knowledge and experience combined with a great attitude will surely win respect.

1fastminivan
02-20-2004, 11:06 AM
Dr. Design, Please come out with the full kit asap!!!:D

Dr. Design
02-20-2004, 12:45 PM
Hello,
We are certainly working on it. We hope to have the interior braces out in about 3-4 weeks.

Thank you all for the support!

Thank you,



Originally posted by 1fastminivan
Dr. Design, Please come out with the full kit asap!!!:D

RiCeCoOkEr1280
02-20-2004, 02:19 PM
D3 Designs Kicks ASS!!!! Customer service is excellent... Thanks James

Paul

fsugatorbait
02-20-2004, 02:24 PM
Originally posted by RiCeCoOkEr1280
D3 Designs Kicks ASS!!!! Customer service is excellent... Thanks James

Paul


haha, just spreading the word in all their threads? :)

RiCeCoOkEr1280
02-20-2004, 02:30 PM
Originally posted by fsugatorbait
haha, just spreading the word in all their threads? :)

hahaha i know i'm whorin'... sorry didn't mean to.... :D

Legolas
02-20-2004, 03:05 PM
This is an interesting thread. As a Scot, there are several things I truly enjoy, one of these is a good argument. Some of the other things include busty women, a good pint, a serious snooker match, football, and, oh yes, of course, auto racing.

There is no question that chasis stiffness is beneficial in motor racing but, any serious driver will tell you that a chasis needs to be somewhat forgiving as well. I disagree when you say that,

" A sway bar, springs, and shocks are not the answer to superior handling".

You are WAY off base in saying this. What the other fellow was saying is that 90% of the drivers out there would be more likely to feel the difference between a suspension upgrade as compared with an x-brace. This I believe to be 100% true.

You also made a comment that suggested that people who do not have x-braces don't drive with passion. COME ON... do you really believe this? That's pretty harsh.

At any rate, the other companies mentioned (Spoon, Mugen etc.)
have undeniable resumes when it comes to racing. Is your R&D department as thorough as theirs?

As the other chap said, it would be interesting to test the various set ups but I will need a little more convincing. I am not altogether sold on the idea of fastenening your tower strut bar to the firewall either. This could create added stress on unwanted parts of the chasis.

Low Rider
02-20-2004, 03:54 PM
Originally posted by Legolas
This is an interesting thread. As a Scot, there are several things I truly enjoy, one of these is a good argument. Some of the other things include busty women, a good pint, a serious snooker match, football, and, oh yes, of course, auto racing.

There is no question that chasis stiffness is beneficial in motor racing but, any serious driver will tell you that a chasis needs to be somewhat forgiving as well. I disagree when you say that,

" A sway bar, springs, and shocks are not the answer to superior handling".

You are WAY off base in saying this. What the other fellow was saying is that 90% of the drivers out there would be more likely to feel the difference between a suspension upgrade as compared with an x-brace. This I believe to be 100% true.

You also made a comment that suggested that people who do not have x-braces don't drive with passion. COME ON... do you really believe this? That's pretty harsh.

At any rate, the other companies mentioned (Spoon, Mugen etc.)
have undeniable resumes when it comes to racing. Is your R&D department as thorough as theirs?

As the other chap said, it would be interesting to test the various set ups but I will need a little more convincing. I am not altogether sold on the idea of fastenening your tower strut bar to the firewall either. This could create added stress on unwanted parts of the chasis.

Exactly!!! Thanks!!!;)

Dr. Design
02-20-2004, 04:32 PM
Hello,
How are you doing? We too enjoy some of the items you have listed. Busty women COULD be one of them. :D

The comment, " A sway bar, springs, and shocks are not the answer to superior handling", is taken out of context. The idea to get people to understand that there is more to handling then just those three items. Chassis flex, bushing deflection, tire compound, cornering weights, etc. All these items are often overlooked. That is what we are suggesting with that comment. Sorry if we caused any confusion or mislead anyone.

We agree chassis bracing is certainly a benefit in racing. It should be understood that the D3 Stiffening components, when installed just by themselves, are not going to give you an overly stiff chassis. It will however give you better performance through stiffening the chassis. When we built our USTCC Racecar we welded in a 6 point cage and still added our Chassis components. Even with a roll cage and our full assortment of chassis braces our chassis STILL has a little give to it. For all intensive purposes we are primarily posting information regarding our "street applications". For our racing stuff we suggest welding all components on the vehicle. Bottom line there is still a certain amount of give in the chassis when adding bracing.

Spoon, Mugen, etc. are all great companies. However the very first full tube chassis racecar in Japan came from one of our engineers. We feel that our engineers are some of the best in the industry. Of course that may be a little bias, so that is why we let our parts establish our reputation.

Again, we too would like to have a comparison done with other companies products to show how our components do against others. We are working with a publication that might allow us to do this.

Please let us know if there are any other questions.
Thank you,










Originally posted by Legolas
This is an interesting thread. As a Scot, there are several things I truly enjoy, one of these is a good argument. Some of the other things include busty women, a good pint, a serious snooker match, football, and, oh yes, of course, auto racing.

There is no question that chasis stiffness is beneficial in motor racing but, any serious driver will tell you that a chasis needs to be somewhat forgiving as well. I disagree when you say that,

" A sway bar, springs, and shocks are not the answer to superior handling".

You are WAY off base in saying this. What the other fellow was saying is that 90% of the drivers out there would be more likely to feel the difference between a suspension upgrade as compared with an x-brace. This I believe to be 100% true.

You also made a comment that suggested that people who do not have x-braces don't drive with passion. COME ON... do you really believe this? That's pretty harsh.

At any rate, the other companies mentioned (Spoon, Mugen etc.)
have undeniable resumes when it comes to racing. Is your R&D department as thorough as theirs?

As the other chap said, it would be interesting to test the various set ups but I will need a little more convincing. I am not altogether sold on the idea of fastenening your tower strut bar to the firewall either. This could create added stress on unwanted parts of the chasis.

Low Rider
02-20-2004, 05:07 PM
Originally posted by Dr. Design
Hello,
How are you doing? We too enjoy some of the items you have listed. Busty women COULD be one of them. :D

The comment, " A sway bar, springs, and shocks are not the answer to superior handling", is taken out of context. The idea to get people to understand that there is more to handling then just those three items. Chassis flex, bushing deflection, tire compound, cornering weights, etc. All these items are often overlooked. That is what we are suggesting with that comment. Sorry if we caused any confusion or mislead anyone.

We agree chassis bracing is certainly a benefit in racing. It should be understood that the D3 Stiffening components, when installed just by themselves, are not going to give you an overly stiff chassis. It will however give you better performance through stiffening the chassis. When we built our USTCC Racecar we welded in a 6 point cage and still added our Chassis components. Even with a roll cage and our full assortment of chassis braces our chassis STILL has a little give to it. For all intensive purposes we are primarily posting information regarding our "street applications". For our racing stuff we suggest welding all components on the vehicle. Bottom line there is still a certain amount of give in the chassis when adding bracing.

Spoon, Mugen, etc. are all great companies. However the very first full tube chassis racecar in Japan came from one of our engineers. We feel that our engineers are some of the best in the industry. Of course that may be a little bias, so that is why we let our parts establish our reputation.

Again, we too would like to have a comparison done with other companies products to show how our components do against others. We are working with a publication that might allow us to do this.

Please let us know if there are any other questions.
Thank you,

I'll say this for you guys: you are courteous and professional to a "T"! Now you've even got me interested in testing your product.
:D

trk
02-20-2004, 05:30 PM
The only problem I have is that I want to try and buy the D3 products BUT, and this is a huge BUT, ... I want to compete in a class of autoX with similiar cars, for example STS and that means no chassis bracing and no firewall mounted bars...

so, in all effect, someone who has a street car and wants to "race" it locally for cheap in a class full of similar cars cant really even buy your products.

How about some SCCA/STS friendly applications?

FCobra94
02-20-2004, 05:45 PM
Originally posted by Low Rider
I'll say this for you guys: you are courteous and professional to a "T"! Now you've even got me interested in testing your product.
:D

And why wouldn't you? All I've heard are good things about this company and their products, so I figure it's worth a try...especially if it's guaranteed ;)

IMO, you really have to try a product out before having certain opinions about it. Otherwise, how would you know whether or not what your saying is valid?

Hearing only good reviews about the X-brace leads me to believe that it's a worth-while investment, otherwise I would be hesitant to even consider it. But that certainly would not lead me to bad mouth it or dismiss it as useless (except in certain circumstances) all togeteher...

I'm eagerly awaitng mine and can't wait to see what changes it will bring to my little EP :D

Low Rider
02-21-2004, 07:04 AM
Originally posted by FCobra94
And why wouldn't you? All I've heard are good things about this company and their products, so I figure it's worth a try...especially if it's guaranteed ;)

IMO, you really have to try a product out before having certain opinions about it. Otherwise, how would you know whether or not what your saying is valid?

Hearing only good reviews about the X-brace leads me to believe that it's a worth-while investment, otherwise I would be hesitant to even consider it. But that certainly would not lead me to bad mouth it or dismiss it as useless (except in certain circumstances) all togeteher...

I'm eagerly awaitng mine and can't wait to see what changes it will bring to my little EP :D

I never "bad-mouthed" these guys or dismissed their product as useless. What I said was that I felt that suspension upgrades would be more noticable to the average driver. I don't think I'm way off base by suggesting that. Sorry if I offended anyone!:angel: