kliemax 3 Report post Posted May 13, 2019 Hi Guys, hoping someone could help me with the rear suspension on my 2007 E90 335i. The ride is rough and you can feel the rear suspension bottoming out on any moderate bump (on Hamilton roads it bottoms out at least once per minute) Car has had the M3 rear camber arm upgrade taking the parts from an E90 M3 - this was done by a previous owner in Japan. Would anyone here know the standard length of an OEM M3 spring for an E90 Sedan? I have been struggling to find this information I measured the springs that are currently in my car - they are 330 MM. I am hoping that my spring is a badly match lowering spring and that an OEM M3 spring will lift the rear 20MM or more to give it the travel it needs. Recently i replaced the bump stops as they were buggered, one was missing and the other was hanging on by a thread. Since doing this it has lifted the car slightly but increased how often it bottomed out. The bump stops were the matching part for shock 3352228431001 which is on the car. As this is the correct OEM part i assume this is not cause of the issue. Can anything think of another reason what would cause this to bottom out? Pic 1 left is an Msport spring from a 135i ( i was told same as an 335i spring) and right, the spring in my car, same height but is significantly ticker / larger diameter Pic 2 M3 rear spring in car model 3352228431001 Pic 3 M3 caber arm Quote Share this post Link to post Share on other sites
Eagle 1662 Report post Posted May 13, 2019 Given its been played with have you had the alignment checked? Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted May 13, 2019 4 minutes ago, Eagle said: Given its been played with have you had the alignment checked? Yes car has had an alignment. Will be due a new one soon but will wait until i finish making changes Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted May 13, 2019 (edited) I took off passenger rear wheel to get some better photos. I'm hoping someone has done this before and can spot something wrong with it Spring / shock mount is that arm upside down? Is anyone familiar with this Mod? Sub frame mountings - could these alter the ride height / suspension travel? Looking from rear, spring mount shock sway bar Edited May 13, 2019 by kliemax Quote Share this post Link to post Share on other sites
Eagle 1662 Report post Posted May 13, 2019 (edited) Ok. Anyway i wouldn't think a spring E87? would be the same as E90 knowing BMW. I used to use cable ties on motorcycle to see what the suspension travel was like, you could probably do the same on the shock. Either way those shocks must of be taking a hiding and if they are aftermarket springs so probably not matched very well. Whats the km's on it? If they are aftermarket lowering springs this may help. Edited May 13, 2019 by Eagle Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted May 13, 2019 you can figure out if the 135i vs 335i spring is the same through checking part numbers on RealOEM. Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted May 16, 2019 On 5/14/2019 at 6:34 AM, Olaf said: you can figure out if the 135i vs 335i spring is the same through checking part numbers on RealOEM. I could do but to be honest but that would only tell me if i was miss guided when i bought E90 M sport rear springs that came labelled with "135" This car has M3 or M3 style thicker springs. I have checked on real OEM before making this post however they do not have a spring for car matching my shock. I was hoping that someone here might just know what they are / should be 1 Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted May 16, 2019 On 5/13/2019 at 10:01 PM, Eagle said: Ok. Anyway i wouldn't think a spring E87? would be the same as E90 knowing BMW. I used to use cable ties on motorcycle to see what the suspension travel was like, you could probably do the same on the shock. Either way those shocks must of be taking a hiding and if they are aftermarket springs so probably not matched very well. Whats the km's on it? If they are aftermarket lowering springs this may help. Thanks Eagle, i will trim my bump stops this weekend and see if that makes a difference Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted May 16, 2019 Buggered shocks can also contribute to bottoming out. Make sure they aren't leaking, but if it keeps bottoming out they're probably poked anyway. Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted May 17, 2019 How did the bump stops "lift the car"? That should concern you more than bottoming out. Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted June 7, 2019 On 5/17/2019 at 10:47 PM, M3AN said: How did the bump stops "lift the car"? That should concern you more than bottoming out. I remeasured it before cutting down the bump stops, ride height was the same so i was wrong here Quote Share this post Link to post Share on other sites
kliemax 3 Report post Posted June 7, 2019 On 5/17/2019 at 8:28 AM, KwS said: Buggered shocks can also contribute to bottoming out. Make sure they aren't leaking, but if it keeps bottoming out they're probably poked anyway. Checked the shocks when i cut down the bump stops, they were firm taking me around 10 seconds to push down enough to get under the shock tower in rear. I'm no expert but i think they are fine for now. No leaks or damage that i could see Quote Share this post Link to post Share on other sites
Herbmiester 923 Report post Posted June 7, 2019 Yes the arm is upside down. One end has a fixed bushing and needs to be installed at ride height as it influences the spring rate because the arm has rotational flex on the bushing. I did the M3 upgrade but went with Tein springs and extra thick pads. I have a vague memory that standard 335i rear springs are quite firm to compensate for the small rear roll bar. Quote Share this post Link to post Share on other sites
Herbmiester 923 Report post Posted June 9, 2019 If they are 135i springs then they have a lower rate than E92 springs 350 lbs/inch vs 456 lbs/inch. Some E92 springs might help. Quote Share this post Link to post Share on other sites