Hullo. I need some help on sway bars and some info to help me decide which bars will be the best for my application. Hopefully the suspension experts around here will be able to shed some light on my questions.
First some info about the car:S14 SE with OEM bars and linksSPL KTS coilovers with 8kg/6kg spring ratesSPL tension rods, TEIN tie rodsOpen DiffStock KA
The car is used for track days, auto-x and drifting. My goals for the car now is to setup the car so that it is fairly neutral handling or slightly biased towards oversteer if possible. Drifting is not the primary goal yet until I build even more skill grip and auto-x and get LSD.
I am really considering the whiteline adjustable bars because I would like to adjust for different applications and tracks but have some questions. The OD of the fronts are the same as the OEM bars that I have, but are they thicker, solid, or otherwise stiffer than OEM? They are adjustable so will I have a range from possibly less stiff than OEM to significantly stiffer than OEM for tuning?
I am trying to get a feel for what the ideal sway bar stiffness is in relation to the coilovers spring rates.I am also trying to get a feel for the handling characteristics that sway bars can change that spring rates and damping rates can't. A local autocrosser explained to me that I will gain grip on the inside rear wheel by stiffening the front sway bar due to a diagonal loading effect. Is this true? If it is can I gain from this effect by increasing stiffness of both the front and rear sway bars to match my coilovers, or does this change only come from changing the proportion between front and rear?
This is important to me because one of my goals of buying new sway bars is to increase rear grip to lessen inside wheel spin from the open diff. The other goal is to learn more about how tuning the suspension before I buy an LSD. My reasoning is that though buying a LSD will eliminate inside wheel spin, I will not learn as much about how to make the car do what I want it to and may even gain new problems that I wont know how to fix.
Another question is related to adjustable end links. I have yet to get my car corner balanced and now I want to wait until I upgrade sway bars with adjustable end links so what I can have the weight distro changed with the bars more then by ride height. It seems there are cheap adjustable end links for the front but the rears are quite a bit more. How much will I be hurt if I get adjustable links for the front but not the rear? It will save me about $100
SPL has the front links for $55 for whiteline front bars, but the links for rear are over $140. Is there any cheaper source for adjustable rears if it will make a significant difference?
Anyway, sorry bout the rambling. Short version. How do the whitelines perform and how large is the adjustability range? Also any fitment issues with upgraded exhaust? Mine is stock now but I don't want there to be a problem when I do upgrade. Any other bars out there that are also adjustable?
Thanks for reading my little book and hopefully for any help. I have done some searching but it has been hard to connect the available info directly to what I want to learn.
sway bar decisions + general questions
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: sway bar decisions + general questions (kclo4)
All sway bars LESSEN the grip by transferring weight.
With 6 kg rear springs [335 pounds per inch instead of oem ~~120 {2.15 Kg}] no after market bar will make much difference because oem 16 mm bar yields ~~ 15 pounds per inch and a 20 mm yields maybe 40........insignificant % increase vs ultra stiff rear springs.
Even a 24 mm rear bar would only be ~~ 100 lbs per roll inch due to the way the bar couples to the midpoint of lower rear suspension arm [divide bar stiffness by 4 to show actual at wheel stiffness].
8/6 kg springs have a stand alone roll couple stiffness ratio of 8/14 or 57% front plus front bar [120?......2.0 Kg/mm max] so you might be as high as 62% front biased..........have an effective front stiffness of 10Kg [500-560 pounds per roll inch depending on bar/spring mount rubber slop].
As an experiment decouple the front bar and see how it behaves and leave oem rear alone or get an adjustable rear only in 22-24mm.
Hard to work with such STIFF SPRINGS.
With such stiff springs you run into to the lack of body frame stiffness issues.
With 6 kg rear springs [335 pounds per inch instead of oem ~~120 {2.15 Kg}] no after market bar will make much difference because oem 16 mm bar yields ~~ 15 pounds per inch and a 20 mm yields maybe 40........insignificant % increase vs ultra stiff rear springs.
Even a 24 mm rear bar would only be ~~ 100 lbs per roll inch due to the way the bar couples to the midpoint of lower rear suspension arm [divide bar stiffness by 4 to show actual at wheel stiffness].
8/6 kg springs have a stand alone roll couple stiffness ratio of 8/14 or 57% front plus front bar [120?......2.0 Kg/mm max] so you might be as high as 62% front biased..........have an effective front stiffness of 10Kg [500-560 pounds per roll inch depending on bar/spring mount rubber slop].
As an experiment decouple the front bar and see how it behaves and leave oem rear alone or get an adjustable rear only in 22-24mm.
Hard to work with such STIFF SPRINGS.
With such stiff springs you run into to the lack of body frame stiffness issues.
Again, this makes me wonder why its so hard to find coilovers for the 240sx with rates softer than 8/6. Most of the softer ones are just cheap street oriented ones, or zeals What's your suggestion Q45tech? How would you set up a 240 for a mix of street and autocross/track day duty? I know thats a broad mix of things, but most people here do drive their cars on the street, as well as going to amateur competitions for fun.