|ncary 0 Report post Posted October 13, 2010 I have just taken this off my car after using it for about a year I believe. (Went back to the stock front sway bar because this one became too much for the lighter engine I have now and the upped spring rates) On an E30 with spring rates near to stock, lowered or not, this will make a dramatic difference to turn-in and inside rear wheel grip. How-to install is here: http://www.bimmersport.co.nz/forums/index....mp;#entry287423 You will indeed need to get some longer 13mm bolts to secure the bushing brackets, otherwise it'll be in there too tight and the bar won't move with the short bolts which are there. Use your stock end links. And grease it up real nice. Bushings have no rips or tears. Retail for about 400 here. On the Whiteline site for 340NZD plus shipping from Australia. Yours, here today, for 240. Quote Share this post Link to post Share on other sites
APT 179 Report post Posted October 13, 2010 What is a stock 325i swaybar size ? Quote Share this post Link to post Share on other sites
|ncary 0 Report post Posted October 13, 2010 19mm. Picking both up.. the weight difference is incredible. Quote Share this post Link to post Share on other sites
polley 916 Report post Posted October 13, 2010 How much would it be for postage to tauranga? Would you take $200? Quote Share this post Link to post Share on other sites
HELLBM 1531 Report post Posted October 13, 2010 What is a stock 325i swaybar size ?Stock 325 is 20mm.Cabriolet is 21mm. Quote Share this post Link to post Share on other sites
|ncary 0 Report post Posted October 13, 2010 Just from postage experience I'd say postage to anywhere in the north island would be north of $30. And at this stage the price is 240, its like that middle ground price which is a good deal for the seller and for the buyer Quote Share this post Link to post Share on other sites
Jacko 2084 Report post Posted October 13, 2010 PM'd Quote Share this post Link to post Share on other sites
Mike 1 Report post Posted October 13, 2010 19mm. Picking both up.. the weight difference is incredible. I assume its the whiteline one thats lighter as it must be hollow? (doubt very much will it be 2.5x stronger than the OEM bar) Quote Share this post Link to post Share on other sites
|ncary 0 Report post Posted October 13, 2010 (edited) The whiteline feels like its twice the weight ha. It's still a solid bar. Around 144% (20 to 25) stiffer according to this chart: http://www.whiteline.com.au/docs/bulletins/010barup.pdf (if the design and materials are the same old vs new, which they are not, so just an estimate in this case) Anyway, SOLD. Going to a good home. Edited October 13, 2010 by Incary Quote Share this post Link to post Share on other sites
Mike 1 Report post Posted October 13, 2010 Huh? How'd they work that out... Sway bar stiffness increases as the fourth power of the diameter. For example, a sway bar might have a diameter of 22mm and you are considering changing it for one which is 26mm in diameter. 224 (22 x 22 x 22 x 22) give a stiffness factor of 234,256 units. The second bar’s stiffness is 264 which is 456,976. Divide one by the other and you can see that the second bar’s stiffness is almost twice (1.95 times) as high, even though it’s only 4mm thicker! ^ Thats how I got 2.5 times stiffer (before I saw that). You're an eng student aren't you? check your notes from 1st pro (I know its sold but I want to know if I'm wrong) Quote Share this post Link to post Share on other sites
CamB 48 Report post Posted October 13, 2010 Be interested to know the answer - have worked on the (non-engineering background) basis in the past that the increase in cross-sectional area of the bar (ie you simply take the change in diameter ^2) is the increase in stiffness. Certainly this is how they get 144% (120% ^ 2). Quote Share this post Link to post Share on other sites
|ncary 0 Report post Posted October 13, 2010 (I'm in intermediate year, 1st year effectively...eeek) Thinking about it practically, if you have a 20mm bar and add 5mm of metal to it, thats a sh*t load of metal being added, and stiffness would increase massively. I can school people on Engineering Statics and Materials?! oh and how to write technical reports. yay Quote Share this post Link to post Share on other sites
Mike 1 Report post Posted October 13, 2010 (edited) Apologies Henry, I thought you were further along than that. Ah, that would be how they got that then but I'm sure its wrong for this application. Basically the material on the outside is more 'effective' at withstanding the stresses applied. good 'ol wikipedia: http://en.wikipedia.org/wiki/Torsion_(mechanics) we're looking at torsional rigidity, GJ. G is the material (which we assume is the same) and J is the size of our bar. Still, doesnt explain how the whiteline one is so much heavier. If its not hollow then it is 2.5 times stiffer, and thats likely to break/bend mounts etc and really screw up handling. Material would make negligible difference in this case so I'm lost. Is the distance the same from the point of rotation to the holes for the endlinks on both bars? Glenn(s)? Ron? Edited October 13, 2010 by Mike Quote Share this post Link to post Share on other sites
Jacko 2084 Report post Posted October 14, 2010 Did I win? Aint got a PM back? But just found out I get a sweeeet discount on new ones anyway Quote Share this post Link to post Share on other sites
JiB 0 Report post Posted October 18, 2010 Yup, Mike's on to it. Just plug numbers into But you'll have to make assumptions about material, etc. With a U-bar, there's always a bending moment about the mounts, which gets bigger the stiffer it gets. But not sure how much it matters on a road car. Quote Share this post Link to post Share on other sites
CamB 48 Report post Posted October 18, 2010 (edited) Well, well, well, will you look at that: Actually in all seriousness, someone should do the maths, coz I can't. Edited October 18, 2010 by CamB Quote Share this post Link to post Share on other sites
