sway and strut bar function?

rubixcubix

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2002 Protege ES Sunlight Silver Metallic
Ok i'm the type of person that needs to know how and why things work before i start spending money to have them changed. I know that sway and strut bars are considered good to have and "improve handling" but i'de like a little more explaination than that. i know strut bars improves stiffness and that stiffer frames provide for tighter handling, but how and why? how does the stiffness of the frame keep the tires from slipping, wouldnt allowing the frame to bend slightly and absorb that energy help reduce the strain on the tires?
i know sway bard reduce body roll, but how? now that i think about it reducing body roll will stabalize the car's momentum in a turn, but again, how does it reduce roll?
Now i did a search on strut bars and found that the mp5 comes with a sway bar. I have a 2002 ES, does that have any sway bars on it? (dont think it does)
Last but not least, if you were me, and considering buying one of the three options (frontsway, rearsway, or front strut) which would you choose to do first and why.
Keep in mind i drive street only, but i do enjoy spirited twisties whenever i can get to them, this is not a track car, and for now i have stock tires (when they wear down im looking at the pirelli pzero neros 205/45/16 cuz someone said they would fit my stock rims)

Hope someone can help!
 
Strut bars keep the car in the correct shape, so the alignment doesn't change under load. Your ES should have front and rear swaybars.
 
Mike R said:
Strut bars keep the car in the correct shape, so the alignment doesn't change under load. Your ES should have front and rear swaybars.
any idea what size?
 
the ES has the same sway bars as the P5, but doesn't have a front strut bar.

think of swaybars by their other name: "anti-roll bars." they prevent roll by tying the two sides of the suspension together. as the car's weight shifts to one side, the suspension on that side compresses and the body wants to lean that way. the sway bar is a torsion bar that's connected to each side of the car and pivots in the middle. kind of shaped like this: |_| with the ends being connected to the struts and the middle part connected to the body and free to rotate. now think about holding an end in each hand and trying to twist the middle. that's what a swaybar does. as the one side compresses, it twists the bar in torsion b/c the other side is not compressing. the stiffness of the bar resists the twisting, transferring some of the weight to the other side and keeping the body more upright.

springs resist roll as well, but not as strongly as a swaybar. springs control body motion with respect to distance- the more a spring compresses, the harder it is to compress even more. so a spring w/ a rate of 100 lbs/in will compress 1 inch when 100 lbs is put on it. to compress it another inch, another 100 lbs is needed.

dampers (struts) resist motion with respect to speed- it's easy to compress a strut if you do it slowly, but the faster you try to compress it, the stiffer it gets. basically what's happening inside the damper is that fluid is being forced through a small hole...ok if it's flowing slowly, but tough to push a lot out quickly.

suspension mods should really be done together...each part depends on the others to do its job properly. i suppose you could start w/ a rear sway bar. the SR motorsports 19mm should be perfect. a decent step up so you'll feel the difference, but it won't require replacing the rear struts (b/c the endlink tabs on the stock struts aren't strong enough to hold a really stiff bar).
 
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ok so i see that a larger rear sway bar would help correct the car's tendency to understeer, what about the front strut tower bar? Does the torsional stiffness of the frame translated directly to handling characteristics like understeer or oversteer?
Did the MP3 have a different rear sway bar and would it work with the stock struts? I wasnt aware that if i change the sway bars i would have to take into account any kind of additional stress on the other components of the suspension.
 
A front strut tower bar "connects" the two front struts together, stiffing up the front end and making turn-in quicker. The car will also track better on the freeway because the two front wheels are tied together by the STB.

You should have no problems with stock struts and a 19mm rear swaybar.:) The MP3 has different struts than our cars, so the tabs that the swaybar attaches to are stronger. I may be wrong, but I believe that the MP3 has the same swaybars that the MSP has...a little bigger than the bars on a P5 or ES. Tokico makes struts for our cars that have stronger mounting tabs for the swaybar if you opt for a 21mm swaybar.
 
would the SR 19mm affect warrent coverage on my suspension? We got the 7 yr 100k mile warrenty cuz this car is going to be with me through college and grad school barring any kind of natural disaster, or any unfortunate incidents with the idiots the DMV issues driver's liscences to.

Good god natey why are we both up so early? i hate having to be at work at 6:45.
 
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The MP3 has a 20mm Racing Beat rear sway bar. You can install it w/ stock struts, but some people have had their strut tabs break as a result. I didn't want to run that risk, so I installed MSP struts.
 
Yes, it will void your warranty. The good news is it's relatively quick & easy to swap back to stock if there's ever a problem. :D
 
rubixcubix said:
Good god natey why are we both up so early? i hate having to be at work at 6:45.
lol, My frickin' neighbor ONLY works on his house from 7-9am....that damn hillbilly.
 
you will never be able to get more stability out of your car frmo any bar aside from

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Natey said:
Yes, it will void your warranty. The good news is it's relatively quick & easy to swap back to stock if there's ever a problem. :D

:: old jewish man voice:: ACHAA! good point! (naughty)

sorry to hear about your neighbor, but my roommate last year snored like a yak so i started wearing earplugs to bed, it helped, that and yelling at him to shut up in the middle of the night. it also meant turning my alarm super loud to make sure id wake up when i actually needed to.
too bad ur not getting paid right now like me (lol2)
 
and as far as the differance in stability .. I could out handle my wifes BMW Z3 covertable Roadster .. also b4 i installed it i took a test run with a buddy Kevin Ford from Lokar Performance .. i took an insanly sharp off ramp at about 45 and almost skidded completley off the road ... and after .. i took him again .. and it just finished raining .. and i was pushing 60 and accelorating through it !!!
 
doesnt that kind of hinder your cargo space? I have to move all of my s*** to a new place twice a year so i dont wanna get one of those trunk cages and i dont have a p5, but damn that sounds like fun to drive!
what is a decent price for a stb and/or a 19mm rear sway?
 
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