Strut/Sway Bars

[KylexD]

I know this has been discussed here and there, but im trying to get it all in one place. I'm wondering what the difference is between the strut, sway, brace, etc. that you can get for your chassis. Is it necessary to have a bar in the front, back, and a brace underneath? Also I'm wondering what's available. I know TRD makes them, then there is also DCSports, and tanabe. Any other manufacturers? And I really want to know who is best for quality.

[ThisorThatxD]

all depends what you want your car to do for you. i personally just have a rear sway bar to help eliminate the body roll and understeer i got after lowering the car. i didnt really need the rest. worked wonders for sharp corners, like on-ramps.

i hear mixed things about front strut bars. some say they work to stiffen up the front, and some say they dont do much of anything. braces underneath (my guess, not experienced with them personally) will stiffen your chassis as a whole, but obviously doesnt interact with the suspension.

i got my bar from http://shop.microimageonline.com/

its the ultra racing rear sway 19mm. most of the parts are also listed under the yaris, but we share the same suspension. they have a scion xD category tho. if you email them they get back really quick as well.

[KylexD]

Ok, so the front is a strut bar, the rear is a sway, and the brace goes underneath. I would imagine with a combination of all 3 then you would be as tight and responsive as possible? Right? And does it matter if say the strut bar is Tanabe, and the sway bar is DCSport does it matter to mix them? And what are the differences in MM, you said you have a 19MM, I have seen people talk about the 20MM???

---------- Post added at 05:27 PM ---------- Previous post was at 04:45 PM ----------

DCSports makes front and rear for the xD.
Front
http://www.autoaccessoriesgarage.com/Suspension/DC-Sports-Strut-Bar/_Item/_324200020
Rear
http://www.nolimitmotorsport.com/prod/CSB2401

These are carbon steel, good quality, and they look nice.


Tanabe has these two items listed for the xD.
Front
http://www.tanabe-usa.com/towerbar.asp
Underbrace
http://www.tanabe-usa.com/underbrace.asp
But nothing listed for the rear?!?!?Hmmm

TRD makes a Rear sway bar from all I find.
http://www.trdsparks.com/displayparts.php?Mdl_dtl=694&Part_cat=11&parts_id=1374


And I'm not sure where to start with Ultra Racing, lol. They have me confused with like 6 diff. bars to choose from.

[ThisorThatxD]

haha yea all of them combined would be the best its getting (unless you find a roll cage). mixing brands is fine. with our cars its even almost necessary due to limited choices. when i say mm i mean the thickness of the bar. my rear sway is 19mm thick. more mm = more stiff. i would say start off with the rear sway bar(not rear strut, as those attach differently). it gave me all i wanted for not too bad a price. obviously if you want more than you can look into more options.

a rear sway will reduce understeer and body roll, giving you more control in the corners. the mm is up to you. the 19mm was more cost effective for me at the time, and its night and day difference than when i had nothing.

[KylexD]

I think what I may do is get the DC Sports so I can get the front and back together, (this depending on what they say back to me, I contacted them to get the specs on them). And then I may add the tanabe underbrace. I will think on it.

[xDTool]

Ok, so the front is a strut bar, the rear is a sway, and the brace goes underneath. I would imagine with a combination of all 3 then you would be as tight and responsive as possible? Right? And does it matter if say the strut bar is Tanabe, and the sway bar is DCSport does it matter to mix them? And what are the differences in MM, you said you have a 19MM, I have seen people talk about the 20MM???[COLOR="Silver"]

And I'm not sure where to start with Ultra Racing, lol. They have me confused with like 6 diff. bars to choose from.

ok so. strut tower bars go on top of the struts, (under the hood over the engine, or in the hatch from strut top to strut top.

sway bars go underneath and connect the left and right from the underneath. theres a rear trd option, and the front already has one (its what those silver links that hook up to the shock arms go to, hence theyre called "swaybar endlinks"

braces..... braces "reduce chassis flex" ........
ive never seen them do anything substantial. i personally dont believe in them. its pretty much a big argument as to whether or not they do anything, some people feel it on their butt dyno when cornering, others find they dont do a damn thing.

as far as strut tower bars go, they are good in cars that have their strut sections away from the body of the car, such as a 240sx, supra etc where theres a spacey engine bay and the wheels sit forward. it helps reduce the left and right side of the car from flexing seperately because there isnt much chassis support where the engine is sitting.

in the xd, strut tower bars will be mostly for decoration. our suspension is built right in front of the firewall and the chassis on the xd is pretty solid as it is.

for swaybars, upgrading both the front and back is good, but only if you carefully figure out what you want to run.

if you just slap 2 big ass bars on the front and back, you will increase your turning capacity and such, but you will miss out on one of the nice tricks about swaybars.

using ratios in swaybar size can help actually reduce/increase oversteer and understeer by changing roll stiffness.

the general idea is if you experience heavy understeer (like the xd's and most other fwd cars do) you pump up the size of the rear swaybar, you will change the roll coefficient of the rear, which will stiffen it up, and help to add an oversteer characteristic to the vehicle..

if you experience heavy oversteer (common in some of the older , heavily powered rwd cars), you pump up the front sway and it helps to balance it the otherway, changing the roll coefficient up front and providing an understeer characteristic.

id say either of the companies 19-22mm sway bars will do just fine for this, and just stick with the stock front sway (not even sure if they make a replacement)

if you get too big with your rear sway you could increase to a point where you start inducing snap oversteer too easily, which is generally a problem for fwd cars, and especially small hatches because the front is so heavy and the rear is so light.


tldr cliffs:

get the rear sway for some performance increase, rear stiffness and to help reduce understeer.

get the others if you want but prepare to be dissapointed.

[KylexD]

LAID SOME KNOWLEDGE DOWN!!! Makes sense, strut bars go on top, sway bars go underneath. "if you just slap 2 big ass bars on the front and back, you will increase your turning capacity and such, but you will miss out on one of the nice tricks about swaybars." What is the nice trick? And basically struts and sways do the same thing, it just depends on your application for what you need. Seeing as you have had a D longer than me, what have you found to be the best? If I dont have to put one on the front, then no need to. I will just do a rear sway bar, Im thinking 20-22MM.

[xDTool]

LAID SOME KNOWLEDGE DOWN!!! Makes sense, strut bars go on top, sway bars go underneath. "if you just slap 2 big ass bars on the front and back, you will increase your turning capacity and such, but you will miss out on one of the nice tricks about swaybars." What is the nice trick? And basically struts and sways do the same thing, it just depends on your application for what you need. Seeing as you have had a D longer than me, what have you found to be the best? If I dont have to put one on the front, then no need to. I will just do a rear sway bar, Im thinking 20-22MM.

the trick is using swaybars to tune oversteer and understeer.

and not quite, the strut tower bar improves the chassis's rigidity between the 2 strut towers. it doesnt actually link the suspension together.

a sway bar actually links the suspension together, when theres no swaybar installed, and you corner, the weight of the car shifts to the outside corner. (ex: if you are accelerating out of a hard right turn , your rear left corner will take on a lot of the weight of the car. the swaybar reduced roll coefficient by "jacking" some of the weight. when the suspension compresses, it basically transfers some of its load through the endlink, through the sway bar itself to the other endlink to the other corner of the suspension, which somewhat compresses the other suspension, reducing roll, and weight transfer to that outside corner. (ex: if you are accelerating out of a hard right turn, your rear corner will take a lot of the weight of the car, the swaybar in turn transfers some of that to the back right corner, compressing the rear right spring/shock, reducing roll.

more on "the trick"
by having a big rear swaybar, you increase the proportion of roll stiffness at the rear axles, which changes the slip angle characteristics of the car. in this particular case the characteristics that the bigger rear swaybar induces is an oversteer characteristic, which in turn helps to reduce the heavy understeer characteristic on most fwd vehicles.

do some googling on oversteer, understeer and swaybars, tons of useful info to be had if you ever plan to do any kind of serious or competitive track/autox racing.

i dont have my d anymore hehe, but i found that the best thing you can really do is just get a good rear sway, microimage and trds both had some really good sways for the rear. between that and a good suspension such as a full trd setup, or a full body coilover setup and a good tire choice will enhance cornering significantly

[ThisorThatxD]

kudos to bob. well more detailed than i could of been lol.

[KylexD]

Right on, breaking sh*t down in here. I couldnt find any specs for the TRD rear sway. But I did find this one from Ultra Racing- http://shop.microimageonline.com/Ultra-Racing-23mm-rear-sway-bar-YARIS-UR-AR23-100.htm Is 23MM too much? Because it will be added to KW V3 coilovers, and im looking for low-profile tires. Having trouble finding those....

[xDTool]

Right on, breaking sh*t down in here. I couldnt find any specs for the TRD rear sway. But I did find this one from Ultra Racing- http://shop.microimageonline.com/Ultra-Racing-23mm-rear-sway-bar-YARIS-UR-AR23-100.htm Is 23MM too much? Because it will be added to KW V3 coilovers, and im looking for low-profile tires. Having trouble finding those....

what size wheels are you using?, 23mm should be fine, i think trd is a 19 or 21mm sway.

[KylexD]

I wanted to stay with 16, dont mind going to 17. Im not too worried with having "Big" wheels. I just want the car to sit nice, i like the low-profile tire look...and dont mind if they are wide either.

[xDTool]

I wanted to stay with 16, dont mind going to 17. Im not too worried with having "Big" wheels. I just want the car to sit nice, i like the low-profile tire look...and dont mind if they are wide either.

my car had 16's on it at 1 point in its life. but not really low profile tires. i think i had a 205/55/16. which is what id go with, and just get a nice tire in that size like a bfgoodrich g force t/a, dunlop direzza star spec, bridgestone potenza, or yokohama advans

my car on 15's
http://farm5.staticflickr.com/4138/4853876798_6d3c51871b_z.jpg

my car on 16's
http://farm5.staticflickr.com/4092/5050227006_8d2ccfa7fd_z.jpg

and on 17s
http://farm6.staticflickr.com/5251/5448967172_6784b10361_z.jpg

[KylexD]

Ok, sweet. I like the 16's, looks nice. I think I will go for that with a little more of a low-profile tire.

[ThisorThatxD]

just know that your speedo/odo will be off with lower profile stuff. here is a calculator for determining that for yea. for example, my new tires will be 205/40/16, so itll be off quite a ways.

http://www.1010tires.com/tiresizecalculator.asp

[xDTool]

just know that your speedo/odo will be off with lower profile stuff. here is a calculator for determining that for yea. for example, my new tires will be 205/40/16, so itll be off quite a ways.

http://www.1010tires.com/tiresizecalculator.asp

yea gotta be careful with that too, the smaller you go the higher speed you will have to show on your speedo to attain a certain speed, so it'll bring your rpms up high.

my accord is like that im running 195/50/15s instead of the oem 195/65/15.... my speedos off by almost 10%

[KylexD]

I may be going 245/35/17 haha

---------- Post added at 01:59 PM ---------- Previous post was at 01:14 PM ----------

I think im getting these wheels. http://www.enkei.com/gw8.html#

[KylexD]

I love these wheels, they are 17x7 w/42mm offset. I will need to find other tires for the wheel though. Im wondering...would I need to add 15mm spacers to make this wheel look right?

[KylexD]

http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+Super+Sport+A%2FS&partnum=04WR7GFASXL&vehicleSearch=true&fromCompare1=yes&autoMake=Scion&autoYear=2010&autoModel=xD&autoModClar= Maybe these tires.

[ThisorThatxD]

your wheels will sit a little sunken in. mine are 17x7 et40 and they are also slightly sunken in. 205 on a x7 is plenty of tire. mine are 205/50/17 to stay close to stock. your call

[KylexD]

Yeah i think I will be getting those wheels, and maybe even those tires too. I think its a good combo....what you think? And what about that offset, you think the 15mm spacer will do the job...or too much?

---------- Post added at 12:25 PM ---------- Previous post was at 12:17 PM ----------

So you have 17x7 40offset, and 205/50/17. Let me see a pic of your wheels.

[ThisorThatxD]

ill have to do it when im home. (stupid work blocking blah). those will definitely go well with your car. not something i would buy but its your car not mine, lol.

id wait on spacers till after you put the wheels on. that way you can get a good measurement. it wont look bad.

[KylexD]

Ok, thats whats up. Ive looked at hundreds of wheels, I cant stop going back to those for some reason.

[ThisorThatxD]

heres a couple shots of them when i was on s techs.

http://a8.sphotos.ak.fbcdn.net/hphotos-ak-ash4/228665_1867069909340_1018817214_2877898_5548854_n. jpg

http://sphotos.xx.fbcdn.net/hphotos-ash4/301250_2149029118144_1018817214_3229896_1011524330 _n.jpg

[KylexD]

Yeah thats nice. So mine would be a little more sunken in, and a little smaller tire.

[matt9112]

well i figure i would chime in and try to contribute....the effect of upper strut bars on chassis rigidity differs car to car...however most cars use the roof-line and A ,B and C pillars to do most of the upper chassis strength...to understand what any of the suspension components do you need to know what forces they are trying to counter act and or decrease/increase. for example on my Honda the upper bars are useless because the pillars are right there there is no flex that high off the suspension...(across towers) a rear lower strut bar would help keep the rear suspension points slightly more rigid but a rear sway-bar reduces the need for such a bar dramatically as it controls roll to a degree....another thing to know is under-steer and over-steer....front sway bars are usually a tad large on fwd cars from the factory so that your grandmother can drive it...by using a smaller diameter front bar you can allow the front end to be looser and reduce "plowing" or over-steer.. from a performance standpoint on a fwd car the goal is to have the rear end extremely tight and the front end looser so the car naturally wants to dive in a bit more and not dive to the outside of a turn...as a real world example i ran a 22mm rear integra type R factory bar and racing end links on my civic and no bar up front at all and i also ran much higher spring and shock rates in the rear than in the front this in effect made the car naturally want to dive into the corner and the rear end was just pulled around with no argument. just my two cents into it....i try to help anyone i can.

[htheduck]

Or for free:
You can pump up the rear tires to 45+ psi to induce a little more oversteer!