Solid vs. Hollow Sway Bars

[csamsh]

So here's a simple (not so simple) question-

Why would one choose to make a swaybar solid or hollow?

The internet comes up with stuff, sure, but I'd like to hear some opinions from people I know or know of.

Thanks!

 

[Roadracer350]

Some people scream weight weither it be sprung or unsprung etc. IMHO their are only maybe 1-2% of the people on this board that can actually tell the diffrence( Terry, Sam etc.) because they are some o the top racers in the country so it actually does not matter to street drivers. Sams bars are hollow and are a good package deal, 3 point adj and mounts to the stock location. Whitelines bars are solid, mounts backwards on the rear end so you can get wider Tyres under the fenders, 4 point adj and comes with adj end links which is stupidly easy to adj on the car. I personally went with Whiteline for the ease of adj and I can get 315-345 under the rear this summer. Now this is just my opinion and it only matters to me but for the bang for the buck you can't beat Whiteline.

 

[NoTicket]

In the interest of semi-scholarly sources, here is a study that was contracted by Whiteline in 2003.

Link

The conclusions of the paper are pretty straight forward. Essentially, solid is cheaper to manufacture and provides a more simple way to produce a defect free bar. The only reason to go hollow is for weight reduction. There is also a minor discussion of just how much sprung vs unsprung mass there is in the bars.

Also, fwiw, that article was written in 2003 and since then a few things have changed. Most OE bars are now hollow. There may have been significant improvements in affordable manufacturing in the last decade. And its conclusion not surprisingly supports Whiteline making exclusively solid bars (which they do AFAIK for all cars they support).

 

[CPRsm]

Not sure how much it goes into the thought process for a swaybar, but hollw would be stronger torsionally than a solid bar. There is more surface are resisting torsion than a solid bar. Same idea applies to gun drilled axles. It saves weight, but makes the axle stronger as well

 

[csamsh]

Not sure how much it goes into the thought process for a swaybar, but hollw would be stronger torsionally than a solid bar. There is more surface are resisting torsion than a solid bar. Same idea applies to gun drilled axles. It saves weight, but makes the axle stronger as well

That's a bit counterintuitive until you actually think about it

 

[Sam Strano]

There is only one reason to do a solid bars. Cost. It's cheaper because they are easier to bend. There is no other benefit unless you are forced to run a solid bar because you cannot run a bigger diameter bar, and the solid is a touch stiffer than a hollow. A little.

It'll get spun lots of ways, like they are massively stiffer, a lot stronger, etc. Thing is, none of that is true. It's a torsion bar, and hollow torsion bars aren't new to the world. When I made my bars there was no way I was going to add weight to make them solid, it's silly to drag around that weight, especially when the front bar on these cars is hollow to start with.

 

[NoTicket]

Not sure how much it goes into the thought process for a swaybar, but hollw would be stronger torsionally than a solid bar. There is more surface are resisting torsion than a solid bar. Same idea applies to gun drilled axles. It saves weight, but makes the axle stronger as well

I'm fairly certain this is only true if the resulting bar is of larger diameter. I don't see what surface area has to do with resisting torsion. When torsion is applied to something it doesn't sit in the surface.

The reason to use hollow is to get a larger diameter bar at a equal or lighter weight.

Maybe I am missing something here...

 

[Roadracer350]

Come on now... Honestly who on here besides top racers( Terry, Sam, Whisky etc ) are going to be able to take advantage of the minimal weight diffrence? I weighed my rear stock bar to te Whiteline unit and I think it was like 1-2 LBS. if you want to loose a couple pounds take a big crap before you hit the track.

 

[jmauld]

Come on now... Honestly who on here besides top racers( Terry, Sam, Whisky etc ) are going to be able to take advantage of the minimal weight diffrence? I weighed my rear stock bar to te Whiteline unit and I think it was like 1-2 LBS. if you want to loose a couple pounds take a big crap before you hit the track.

I thought the rear stock bar was solid?

 

[zeroescape]

I think cprsm was refering to cross sectional area. Obliviously same diameter hollow bar has less cross sectional area opposed to a solid, but most of the torisional resistance sit on the outer third of the diameter. In terrys vorshlag thread i believe he weighed the solid front sway bar from whiteline and the comparison can be seen vs stock bar.

Edited. I looked it up:

Whiteline 33mm solid front swaybar is 21.5 lbs
Stock OEM 35mm hollow front swaybar is about 13.8 lbs (with the bracket and bushings, i didnt cut them off)

 

[NoTicket]

Come on now... Honestly who on here besides top racers( Terry, Sam, Whisky etc ) are going to be able to take advantage of the minimal weight diffrence? I weighed my rear stock bar to te Whiteline unit and I think it was like 1-2 LBS. if you want to loose a couple pounds take a big crap before you hit the track.

Who cares if you can "take advantage of it"? Why would you buy something heavier and more expensive given the choice?

I understand the reason for going with the Whiteline rear bar to get more clearance but this top racer stuff is bullshit. A lighter set of bars is clearly more desirable. AFAIK there is no advantage to using the front Whiteline sway other than to have matched set and you really needed the rear Whiteline bar.

 

[Roadracer350]

Who cares if you can "take advantage of it"? Why would you buy something heavier and more expensive given the choice?

I understand the reason for going with the Whiteline rear bar to get more clearance but this top racer stuff is bullshit. A lighter set of bars is clearly more desirable. AFAIK there is no advantage to using the front Whiteline sway other than to have matched set and you really needed the rear Whiteline bar.

Just because somthing is lighter does not mean its always better. I learned that road racing bikes. You can put lightned parts on your car all day long and when you ACTUALLY start beating on your car at the track usually the first things to break at race pace are the lightned parts. We built titanium this and titanium that for the bike and yes she was light as hell. 370LBS ful of fuel and 191hp at the rear tire an you want to know what started breaking first.. All the lightned stuff. We took the bike to the Isle of Mann and I made 3 laps and stuff started breaking. We had to replace parts with heaver stock parts and purpose built heavy parts just to make it around and the weak part wound up being the hot rodded lightned motor. For every hour of rideing/driving you will have an hour or more of maintance. Just because it's light does not mean its better an when your crusing around at the local hangout with your light parts an blasting the highway your not going to tell 1 bit of diffrence. Sams bars are top notch from what I have been told. The Whiteline front bar also comes with adj end links, lateral locks and is 4 point adjustable. You don't need extra clamps because the mounting points flex until you get a brace put in and the BMR raid mounts bend from what I have read but I think they have fixed that by adding bigger gussets. The point being if your running around on the street with full interior, AC yadda yadda yadda how are you going to tell the diffrence between a hollow bar and a solid one? I will tell you how... In your mind. It's not going to turn in faster, ride smoother, take 5sec off your time from McDonalds to WalMart it's all in your mind. Now I'm not saying that's what you do or how you drive I'm just using this as a reference. Theirs other ways to take weight off the car but then that depends on the orginasation and class your racing in. Look at Terry's red car. Whiteline everything, full interior, AC and he is still podium at national levels. Sam is the same way but how can you sit here and say that we could tell the diffrence. Take the front seat out and replace it with a Carbon Kevlar Sparco unit and you take MORE than the front and rear bars combined out of the car and tell me if you or I could tell the diffrence. Terry, Sam, Whiskey etc could but you or I doubt it.

 

[NoTicket]

I am not arguing that you could or could not tell the difference. I am saying that whether or not you can tell the difference is a poor metric to use when making recommendations or for defending it.

I am not a weight reduction freak. My car is completely stock except for a Watts Link and the MGW Shifter. But if I were going to be buying a replacement sway bar I would go with a lighter tubular bar over a solid one all else being equal, because of the weight savings.

I'm not saying that the Whiteline kit is bad (I am still considering it). I like Whiteline's bushings. They are nice and silent and stiff. But being heavier is a bad thing, and you can't just do some hand waiving, claiming unless you are a pro you won't notice, and have it not matter.

 

[zeroescape]

Just because somthing is lighter does not mean its always better. I learned that road racing bikes. You can put lightned parts on your car all day long and when you ACTUALLY start beating on your car at the track usually the first things to break at race pace are the lightned parts. We built titanium this and titanium that for the bike and yes she was light as hell. 370LBS ful of fuel and 191hp at the rear tire an you want to know what started breaking first.. All the lightned stuff. We took the bike to the Isle of Mann and I made 3 laps and stuff started breaking. We had to replace parts with heaver stock parts and purpose built heavy parts just to make it around and the weak part wound up being the hot rodded lightned motor. For every hour of rideing/driving you will have an hour or more of maintance. Just because it's light does not mean its better an when your crusing around at the local hangout with your light parts an blasting the highway your not going to tell 1 bit of diffrence. Sams bars are top notch from what I have been told. The Whiteline front bar also comes with adj end links, lateral locks and is 4 point adjustable. You don't need extra clamps because the mounting points flex until you get a brace put in and the BMR raid mounts bend from what I have read but I think they have fixed that by adding bigger gussets. The point being if your running around on the street with full interior, AC yadda yadda yadda how are you going to tell the diffrence between a hollow bar and a solid one? I will tell you how... In your mind. It's not going to turn in faster, ride smoother, take 5sec off your time from McDonalds to WalMart it's all in your mind. Now I'm not saying that's what you do or how you drive I'm just using this as a reference. Theirs other ways to take weight off the car but then that depends on the orginasation and class your racing in. Look at Terry's red car. Whiteline everything, full interior, AC and he is still podium at national levels. Sam is the same way but how can you sit here and say that we could tell the diffrence. Take the front seat out and replace it with a Carbon Kevlar Sparco unit and you take MORE than the front and rear bars combined out of the car and tell me if you or I could tell the diffrence. Terry, Sam, Whiskey etc could but you or I doubt it.

I would think we could leave peoples driving skills out of the picture and talk objectively about tech instead of kiss assing a bunch of your favorite drivers.

Its supposed to be a forum to educate each other to better ourselves.

Breaking a sway bar is out of the question, unless you hit a wall or curb.

This is the whole game of racing, trying to go fast a possible. Eventually yes you break something. It happens to the pros, but sitting here telling people youll never get the performance out of a part is silly.

This is the corner carvers forum not some concours trailer queen parade.

 

[SoundGuyDave]

I would think we could leave peoples driving skills out of the picture and talk objectively about tech instead of kiss assing a bunch of your favorite drivers.

Its supposed to be a forum to educate each other to better ourselves.

Breaking a sway bar is out of the question, unless you hit a wall or curb.

This is the whole game of racing, trying to go fast a possible. Eventually yes you break something. It happens to the pros, but sitting here telling people youll never get the performance out of a part is silly.

This is the corner carvers forum not some concours trailer queen parade.

Agreed, 100%. For the record, I have Sam's sways on mine, but what REALLY matters is the effect on wheel rate. So, in a theoretical case, let's say you have two bars, one solid the other hollow, that have EXACTLY the same effective spring rate. Now, the question becomes which to buy? Given that neither bar will break in half from ordinary usage, then it becomes a slam-dunk decision to get the physically lighter component, unless there is another "X" factor involved. Up front, there is PLENTY of room, so the increased diameter of the hollow bar is a non-issue. In back, if you need the space for gumballs, then the reversed-solid bar suddenly has something going for it that the standard-hollow bar does not. Up front, though, you'd be an idiot NOT to try to get as much weight off the nose as possible WITH AN S197 CHASSIS. To me, this becomes a pretty simple argument.

 

[jmauld]

Just because somthing is lighter does not mean its always better. I learned that road racing bikes. You can put lightned parts on your car all day long and when you ACTUALLY start beating on your car at the track usually the first things to break at race pace are the lightned parts. We built titanium this and titanium that for the bike and yes she was light as hell. 370LBS ful of fuel and 191hp at the rear tire an you want to know what started breaking first.. All the lightned stuff. We took the bike to the Isle of Mann and I made 3 laps and stuff started breaking. We had to replace parts with heaver stock parts and purpose built heavy parts just to make it around and the weak part wound up being the hot rodded lightned motor. For every hour of rideing/driving you will have an hour or more of maintance. Just because it's light does not mean its better an when your crusing around at the local hangout with your light parts an blasting the highway your not going to tell 1 bit of diffrence. Sams bars are top notch from what I have been told. The Whiteline front bar also comes with adj end links, lateral locks and is 4 point adjustable. You don't need extra clamps because the mounting points flex until you get a brace put in and the BMR raid mounts bend from what I have read but I think they have fixed that by adding bigger gussets. The point being if your running around on the street with full interior, AC yadda yadda yadda how are you going to tell the diffrence between a hollow bar and a solid one? I will tell you how... In your mind. It's not going to turn in faster, ride smoother, take 5sec off your time from McDonalds to WalMart it's all in your mind. Now I'm not saying that's what you do or how you drive I'm just using this as a reference. Theirs other ways to take weight off the car but then that depends on the orginasation and class your racing in. Look at Terry's red car. Whiteline everything, full interior, AC and he is still podium at national levels. Sam is the same way but how can you sit here and say that we could tell the diffrence. Take the front seat out and replace it with a Carbon Kevlar Sparco unit and you take MORE than the front and rear bars combined out of the car and tell me if you or I could tell the diffrence. Terry, Sam, Whiskey etc could but you or I doubt it.

You sound like you're just justifying your decision. There is NO reason to buy a solid bar, when the car came from the factory with a hollow front bar, AND there are good aftermarket options that do not ADD weight.

Besides, a few pounds here and there add up to a lot of weight overall. It's fairly easy to get 150lbs out of these cars, which most drivers can feel. And if you're selective about the parts, you can do it without destroying the driveability of the car.

 

[Roadracer350]

I would think we could leave peoples driving skills out of the picture and talk objectively about tech instead of kiss assing a bunch of your favorite drivers.

Its supposed to be a forum to educate each other to better ourselves.

Breaking a sway bar is out of the question, unless you hit a wall or curb.

This is the whole game of racing, trying to go fast a possible. Eventually yes you break something. It happens to the pros, but sitting here telling people youll never get the performance out of a part is silly.

This is the corner carvers forum not some concours trailer queen parade.

No one is ass kissing anyone. I am giving them the respect as a racer they deserve. As for driving skills I was not talking about his, yours or anyone else's I just pulled it out of the air. As for breaking a bar I never implied a hollow bar would break. Never even heard of a bar breaking, bending in a crash yes but not breaking. My statement was my opinion and it may be wrong and differ from yours and that's cool. The reason I chose the Whiteline front bar was price, adjustability, end links, lateral locks, customer service and I already had all their other parts.

 

[SoundGuyDave]

No one is ass kissing anyone. I am giving them the respect as a racer they deserve. As for driving skills I was not talking about his, yours or anyone else's I just pulled it out of the air.

Not trying to bust your balls, but it sure SOUNDED like you were saying that unless you're Terry, Sam, or have a national title, there's no way you'll feel a weight reduction in the car. Now, for a 5-10lb net difference, I'd be inclined to agree with you. But "it's only 5lbs" multiplied by swaybars, hood, wheels, brake rotors, etc. etc. can add up to SERIOUS weight. Take two former TTB S197s... Both were at min weight (I'm pretty sure) in 2010, and then things changed. Now, one is around 3700lbs, and the other is 3300. And yes you CAN feel 400lbs, even without a national title. Terry, Sam, et al all certainly deserve the props they get as drivers (as well as testers and reviewers), but just because they have a specific part on their car doesn't necessarily mean that it's the optimal solution. Take the Vorshlag-mobile as an example... Yes, it's a VERY well put together TT car, but besides being Terry and Amy's competition vehicle, it's also a rolling demo-room for a lot of the parts lines that Terry sells. THAT right there easily trumps the weight differential.

As for breaking a bar I never implied a hollow bar would break. Never even heard of a bar breaking, bending in a crash yes but not breaking.

And again, yes you kind of did imply it when you brought up your titanium IoM bike failures. While I agree that lighter is not necessarily better, there was no reason to even bring up the example unless you were trying to imply that a tubular (lighter) swaybar may have the same durability issues. With the wall thicknesses needed to give the correct "spring rate," there's no chance that simple use or basic track abuse will cause it to shear in half.[/quote]

The reason I chose the Whiteline front bar was price, adjustability, end links, lateral locks, customer service and I already had all their other parts.

Excepting the last one, all very good reasons to buy the Whiteline setup. "I already had all the rest of the parts" to me is never a good reason to just pony up for something blindly. Wile I don't (yet) have any Whiteline parts on my car, I have suspension components from Freedom Racing, Steeda, Strano, Maximum Motorsports, BMR, AST, Hyperco, FRPP, etc. Why? I assessed each individual part as they related to the whole system, and chose what I thought would do the best job.

I'm really not trying to bust your balls, I'm just pointing out that what and how you post can have a profound impact on the message you're trying to convey...

 

[Whiskey11]

Come on now... Honestly who on here besides top racers( Terry, Sam, Whisky etc ) are going to be able to take advantage of the minimal weight diffrence? I weighed my rear stock bar to te Whiteline unit and I think it was like 1-2 LBS. if you want to loose a couple pounds take a big crap before you hit the track.

I'm STILL not sure why my name is being used in the same as Sam and Terry... I'm a nobody in comparison to those two! Those two combined probably have more National Tour stops and wins than I have events in my entire autocross career. About the highest person on the list I'd feel comfortable being mentioned with is Norm and I say that because he and I approach problems in a similar manner but I'm 99% sure he's a better driver! I'm vocal, and that is my "claim to fame"... I guess you could add the only person to take an S197 to Nationals in STX which either makes me crazy or stupid, or most likely both!

Anyway, I personally think that there is no reason to go to a solid swaybar setup when it can be avoided due to the weight reasons. That is most likely 100% related to the fact that I race in a class where the "race to the bottom" for weight is still very active and anything to reduce or minimize weight gain is crucial in all but the most important of modifications (weight gain from a Torque Arm and weight gain from the Watts link for instance). Since Sam has a nice set of bars out for these cars, there is no reason to run solid bars except for "MOAR TIRE!" Good news is that all the autocross classes that allow "MOAR TIRE!" also allow sawzall modifications to fenders for those who really want "MOOOOOAAAAAAAAAAAAAR TIRE!".

 

[Roadracer350]

I didn't mean to imply anything. It's just my opinion. Yes weight reduction is a good thing and I agree but what I was trying to say was that unless you are racing the crap out of your car and are trying to get the lowest possible weight and trying to shave tenths off your lap times are you really going to bennifit from a hollow bar. Most people will not be able to feel the weight diffrence between a hollow or solid bar when it's installed. The reason I chose the Whiteline set up is because I wanted an entire kit that I know was desighned to work together. I looked up Griggs, Cortex and Whiteline. They are all top notch but Griggs and Cortex are stupid expensive and Whiteline was a decent price and still top notch kit. I looked and even talked to Sam about his bars but in the end I wanted a car with everything front to tear that was designed to work together plus the parts obviously works because Terry has proven it and the guys at Vorshlage has AWSOME customer service. I can run down to Eagles Canyon or Cression and they will most likely be their and I can pick their brain and get help on the set ups. I am not saying that solid bars are better and yes their is a weight diffrence but to the average street guy he is not going to tell the diffrence. To the racer that is shaving a ton off yes but a diffrence of 5LBS... On a bike yes you will feel it but a car I can't see it. 400lbs hell yes but 5... Now like you said combine that 5 with 3 here and 10 their etc then yea. Oh and I am the guy that wants MMMOOORRREEE TIRE! The car I drove at Hallett had 295s and I was pushing the front thru most corners but not sure if that was down to tires or me trying bike lines and corner speeds.