sway bars vs strut bars

[apzak]

I have about 250-300 dollars and I was thinking about getting either sway bars or strut bars. What's a more noticable upgrade and removes most of the body roll? What's easier to install? I'm not sure on what swaybars I want yet, but am set on front and rear cusco type os strut bars. I have a 98 240sx SE with 55,000 miles and just want to take some body roll away and be able to push the car harder into turns. From what I read, having an SE means I have factory swaybars so I'm leaning towards the strut bars.

[240marcuSX]

for better handling and less body roll = sway bars, without a doubt, cheaper too

easier to install = strut bars

i forgot how much they are, but the suspension techniques are a nice choice and come as a pair, pretty easy to install, if you end up getting them the advice that i have for you is, USE ANY FACTORY BOLTS THAT YOU CAN!, especially the ones that bolt to the underbody and actually hold the bar in place.

[Ceptos]

strut tower bars stiffen the chassis. the way i see them, is i plan on getting them as one of the last pieces, after other chassis stiffeners like harder bushings.

i cant speak for suspension techniques, but whiteline sells a set of adjustable bars, they come with hard bushings, adjustable links and link hardware. front and rear can he had for $330 at pdm racing, thats the set i plan on getting.

[Checkered-Member]

go here: http://www.importpartsusa.com/....htmlYou can get both a front and rear sway bar for under 250, with the 50 buck left over go to eBay and buy a generic strut bar for around $50, I have one and it does make a difference. Don’t over pay for a brand name.

So there you go for 300 you can get all three.

[Q45tech]

Generally sway bars are not stiffer than springs [usually 20-45% of spring stiffness].......the low end = oem and the higher end aftermarket performance.

At best new sway bars only reduce sway [body roll] by 20-30%.You select springs to do 75% of what you want then fine tune with sway bars.

[ColumbusDrift]

I would definetely recommend the whiteline swaybars. after i put them on i noticed a huge difference in the amount of (lack of) body lean and such when taking corners fast. as for obtaining them try to find someone besides pdm racing because i didn't have a great experience with that company.

[apzak]

oh man, im looking at cuscos sway bars... bling bling. looks like the cuscos are thicker than the whiteline. If I got shocks/springs everything under the car that has to do with suspension gets taken appart, right? sway bars would have to come off, and it would be best to replace the brushings with polyurethane ones so maybe i should do the sway bars when i do shocks/springs/brushings? I also heard with springs/shocks you'll need strut bars to help the chassis with the added stress so if I got strut bars i'll be ready for serious suspension modificaitions, and atleast i'll have a taste at what something minor like strut bars will do. so what do you think? will I be fine going strut bars first? I'm taking my car to a show in two weeks so if I have them by then that would be even better. i doubt i'll rank high, just curious what judges will say i have tons of scratches on my paint so i'm not expecting a trophy.

Quote »as for obtaining them try to find someone besides pdm racing because i didn't have a great experience with that company[/quote]

fill me in because as of now if i go whitelines thats where i'll get them from

[Ceptos]

i would save the money for something else, tires/wheels and a good alignment would be a nice start to suspension work, after that i would go for springs/shocks. you could reverse the order, but those are the two main improvements. i didnt unhook anything besides the strut when i replaced mine. tho its a good idea to replace all the bushings at once, that can get expensive, where i live at least. maybe im thinking about this wrong, but it doesnt seem like a strut bar would be noticable to someone who isnt seriously pushing their car, enough to make the stock chassis bend. they also seem like they should be installed in pairs, instead of just the front.

on the topic of thicker sway bars...at what point will a sway bar hurt preformance? i know they can start to act like a solid axle, linking the two sides together and working to lift the inside tire off the road surface, but at what point does this become a consideration?

[maxnix]

on the topic of thicker sway bars...at what point will a sway bar hurt preformance? i know they can start to act like a solid axle, linking the two sides together and working to lift the inside tire off the road surface, but at what point does this become a consideration?

Q45tech answered that a few posts above!

[Ceptos]

i didnt see anything about being too stiff...how do i compare '20-45%' when its millimeters and kiligrams?

[MrFox]

at what point does this become a consideration?

It depends... on one end of the roll stiffness spectrum you have the detroit land yachts that roll and heave like an old pirate ship. on the other end you have go karts with infinite rate "chassis flex" suspension.

Roll does 2 things to the chassis that is bad for cornering. It shifts the C.G to the outside slightly, and (more importantly) it chambers the wheels in the wrong direction. So the benefits of increasing roll stiffness is dependent 2 chiefly on 2 factors: the C.G height of the vehicle, and the degree of chamber compensation built in the suspension design. In general, struts tolerate little roll comparaed to double A-arms.

[Ceptos]

i dont want to sound rude in any way, but i know what the affects of body roll are =) what i mean is, when you corner with a sway bar, it works to pull the inside tire 'up' so it can keep the outside tire 'down'. this links the two tires together, and takes away from the advantages of independent suspension. in a solid rear axle car, when exiting a corner fast enough the inside rear tire will be unloaded, or possibly off the road surface, so your exiting acceleration is affected, a sway bar will work to do the same thing. if its possible in track cars, a rear sway bar isnt used at all.

i doubt this is a consideration with most aftermarket sway bars since they are made for a variety of setups.

[Q45tech]

Nissan rear suspension has roughly a 0.8 degree per inch of camber correction.+3 inch = -1.5 static +[-3x0.8] = negative 3.9 degrees+2 inch = negative 3.1 degrees+1 inch = negative 2.3 degreesloaded normal ride height what ever you set static.....normally negative 1.5 degrees.

Lowering the rear throws this [the camber curve] all off as when the normal ride is passed thru the tire goes more positive [less negative camber].

On a street car there in little wrong with having the rear move +- 3.0" in severe transistions [lane changes] if the shocks are new and in control so that there is no overshoot or oscillations. Uncontrolled tail wagging!

Rear sway bars are added without stiffening shocks, this is bad because in emergencies the rear is not properly damped.

Why you match springs and shocks and try not to have the sway bar added more than 25% [uncontrolled spring action].

The camber curve is designed in to fit the sidewall stiffness of oem tires more or less or tires are used that are close to the camber curve.

Even Tokicio blues with Eibachs [only 20% stiffer] wear fast and by 15-20,000 miles the shocks have lost precise contol in rebound from the extra energy dissipated from the stiffer springs.

They feel too stiff new but quickly soften [beakin] then down hill fast. Adjustable rear shock allow you to click them to stiffer as they wear in, every 10k.

[MrFox]

in a solid rear axle car, when exiting a corner fast enough the inside rear tire will be unloaded, or possibly off the road surface, so your exiting acceleration is affected, a sway bar will work to do the same thing. if its possible in track cars, a rear sway bar isnt used at all.

Roll stiffness doesn't have anything to do with whether you have a solid rear axle. A live axle is unsprung - the chassis is free to roll on it.

Some solid axle cars have anti-roll bars.

You are correct regarding inside wheel lift and exit acceleration. But there are plenty of reasons for the sway bar's existance on a track car.

[Q45tech]

Most large RWD have a rear sway bar: Crown Vic, Mercury, Lincoln - police cars and taxi had solid rear axles till recently, same with Mustang and Camaro. Even the Lexus 400 had one [a tiny one in 1989 which got stiffer each model iteration].

Only the 90-96Q in standard form didn't come with one because they assumed Americans were smart enough to order the touring version..if they wanted superior handling FEEL..........boy were they wrong!..........about the typical Americans understanding of vehicles.

[apzak]

how much of a weight difference is there between the :

front type os vs front carbon fiber rear type os vs rear carbon fiber?

maybe i'll go rear carbon fiber and apexi front because it's supose to be as light as the carbon fiber.

[Mayhem_J30]

how much of a weight difference is there between the :

front type os vs front carbon fiber rear type os vs rear carbon fiber?

maybe i'll go rear carbon fiber and apexi front because it's supose to be as light as the carbon fiber.

Another question would be, if the same size of two different materials, do they offer the same resistance? Some how I don't think so.

[Snarlynx]

I know carbon fiber is strong... but is it strong enough for an effective sway/stur bar? Seems like it would have to be super thick.

P.S. W00t!!1 the 10,000 post here!

[apzak]

Another question would be, if the same size of two different materials, do they offer the same resistance? Some how I don't think so.

true, damn who would have known picking a strut bar would be more complicated than picking a header? guess there are too many options out there, and different designs. i'll stick to type os because it's cheaper, people seem to love it's fit, and im not going to make my car lightweight like i originally planned.

oh, and i'm going to do sway bars some other time because the other day i had the car on the lift to get it's oil changed and saw the rear sway bar looks simple to replace, but the front one is more difficult to see, looks alot more difficult to replace. same as brushings, damn there are alot. doesn't look like something i could do myself. i have some small surface rust forming on the rear sway bar too.. and my cars only a 98:(

[LittleBrotherSilvia]

sway bars are easy to replace, shocks/springs are also if u have the right tools (which u can get from autozone for a deposit), and if u cant put a strut bar on urself u have a serious problem

the cusco carbon fiber strut bars arent made of JUST carbon fiber, they are aluminum WRAPED in carbon fiber, which would be plenty strong, but not worth the price as they are pretty much only for looks.

i've upgraded all of my suspension aside from my stock sways, and i'll probobly be goin with whiteline on those.

[Mayhem_J30]

true, damn who would have known picking a strut bar would be more complicated than picking a header? guess there are too many options out there, and different designs. i'll stick to type os because it's cheaper, people seem to love it's fit, and im not going to make my car lightweight like i originally planned.

oh, and i'm going to do sway bars some other time because the other day i had the car on the lift to get it's oil changed and saw the rear sway bar looks simple to replace, but the front one is more difficult to see, looks alot more difficult to replace. same as brushings, damn there are alot. doesn't look like something i could do myself. i have some small surface rust forming on the rear sway bar too.. and my cars only a 98:(

Oops, I thought you were talking about Sway bars and not STB's. The flex difference will be minimal considering the flex between the towers is already minimal to begin with.If you truly want to add a STB with minimal weight and don't mind paying the price go with Titanium.

[MrFox]

If you truly want to add a STB with minimal weight and don't mind paying the price go with Titanium.

Titanium is actually a poor choice for structual bracing applications.

Density (lb/in3): Lightest->Heaviest1)Carbon Fiber (AS4/3501-6) - 0.0572)Aluminum (2024) - 0.1013)Titanium (MILT) - 0.1594)Steel (1025) - 0.282

Stiffness (Msi): Stiffest->Flexiest(?)1)Steel - 302)Carbon - 20.63)Titanium - 15.74)Aluminum - 10.4

Stiffness to Weight ratio (E/d)1)Carbon - 361.402)Steel - 106.383)Aluminum - 102.974)Titanium - 98.74

However, most carbon pieces out on the market are made for looks. The strength and rigidity of carbon depends greatly on the way it is layed up, and most people have no clue on how to do it properly (probably because most buyers don't have a clue either)

[Mayhem_J30]

Good info MrFox. Do you have and good links to lists of physical properties of metals? or things like CF?

Titanium is actually a poor choice for structual bracing applications.

Density (lb/in3): Lightest->Heaviest1)Carbon Fiber (AS4/3501-6) - 0.0572)Aluminum (2024) - 0.1013)Titanium (MILT) - 0.1594)Steel (1025) - 0.282

Stiffness (Msi): Stiffest->Flexiest(?)1)Steel - 302)Carbon - 20.63)Titanium - 15.74)Aluminum - 10.4

Stiffness to Weight ratio (E/d)1)Carbon - 361.402)Steel - 106.383)Aluminum - 102.974)Titanium - 98.74

However, most carbon pieces out on the market are made for looks. The strength and rigidity of carbon depends greatly on the way it is layed up, and most people have no clue on how to do it properly (probably because most buyers don't have a clue either)

[MrFox]

I got the above data from my composites textbook.

A good (free ) online source of material data:http://www.matweb.com/

[apzak]

great now i'm more confused. if aluminium is so flexible, why would cusco use it in all their strut bars?

Quote »The flex difference will be minimal considering the flex between the towers is already minimal to begin with.[/quote]is this still true when you have a grippy tire, aftermarket shocks/springs, and swaybars? if so, why does tirerack recommend getting strut bars for heavily modified suspension because of the added stress to the chassis? are they just saying this to make money, or do you really need them when you have upgraded suspension?

[Mayhem_J30]

great now i'm more confused. if aluminium is so flexible, why would cusco use it in all their strut bars?

is this still true when you have a grippy tire, aftermarket shocks/springs, and swaybars? if so, why does tirerack recommend getting strut bars for heavily modified suspension because of the added stress to the chassis? are they just saying this to make money, or do you really need them when you have upgraded suspension?

I'd use it as a final touch piece. Of course like you said with 'tighter' suspension other things will begin to give more. But to be able to actually drive the car to it's limits and be able to notice the difference between chasis flex vs no chasis flex....you get what I"m saying, right.Why does tirerack say that, well they want to sell stuff. They'll also sell you some stock sized cross drilled rotors that'll do nothing but put your life in danger. But so will every other vendor out there.Like Q45tech said. Work with your dampening first, then fine tune with some sway bars then throw on your STB's. Of course STB's are cheap so it won't hurt anything now.Do a google search for "aluminum vs. titanium vs. steel" a lot of bicycle forums/threads will appear offering good info on the properties of the above. Fatigue, flex, price and practicality all seem to play a role. It's more than I had time to read and soak in so I'll have to dive into it more later. It's quite interesting as they all seem to have specific strengths and weaknesses that are completely different from each other.

[MrFox]

great now i'm more confused. if aluminium is so flexible, why would cusco use it in all their strut bars?

is this still true when you have a grippy tire, aftermarket shocks/springs, and swaybars? if so, why does tirerack recommend getting strut bars for heavily modified suspension because of the added stress to the chassis? are they just saying this to make money, or do you really need them when you have upgraded suspension?

Structural stiffness is dependent not only on material stiffness, but also on cross-section thickness. Because of its lower density, an aluminum bar can be made thicker and stiffer than a steel bar of the same weight.

The car may be flexing more with added stress from modifications, but it isn't going to snap in half anytime soon. Like the remainder of your modificaitons, what you "need" is dependent on what you "want".

Is the chassis leaving you "wanting" for more rigidity?