My car it's unsafe in highway

[diegom6]

So I tookt he bimmer finally tot he highway for proper tune up. For some periods I was runing about 200-220 Km/h or so, but even slower than that my car "copy" too much the irregular surface of the roads and kinda making my car bit unstable.

I figured could be due the very reduced travel I do have since the car seats low on the ground. I think it's bottoming out the suspension, and when there is no more spring coil collapse or travel anymore, must be the contact of it with the bumpstop or whatever it's called making myc ar "jumpy" in certain conditions , mostyl when i hit too fast a kind of hole, but it's not a pothole int he road, it's just a deformation of the ground if you know what I mean ( don't have the word in english).

Also, it hits when I do drive in town and just pass through "connections" of blocks of the road at certain speeds or when I go downhill , about 30-40 degrees and the road get stright, in that angle the suspension compress and therefore "hit" if I go enough speed.

I'm either, get larger springs or harder, or just increase the height of the car witht he current coil springs by adjusting the collar just.

The Konis are set stiff

My setup:

Konis yellow sports adjustable

OBX Coil over e36 fitte din a e30 (I know this is crap comapred to well brand names)

Vorschlag camber plates

Stock swaybars

Any input?

-Diego

[jlevie]

What you are describing sounds like tramlining, which is the tendency of the car to follow imperfections in the road. That is caused by improper alignment or the tires in use. It won't be caused by the suspension bottoming out.

[JGood]

All of your bushings and ball joints in good shape as well?

[golde30]

what kinda tires you runnin?

[diegom6]

All my tie rods and balljoints are fine.

I'm runing brand new Dunlop Direzza 215-50R16 on back and 205-50R16 on front. 33 PSI cold

[atomic]

I would raise it back up some and soften the Koni's and see how it behaves on the highways before throwing more cash into it...

[318isbmw]

Mine used to do that, had it alligned and they took out some of the negative camber in the front(lowered it on Ireland's) and it did much better

[diegom6]

Messures from the lip of the wheel in both cases:

Front Left : 21" - 53 1/2 cm

Front Right: 20" 3/4 - 53cm

Rear Left: 21" 1/4 - 54cm

Rear Right : 21" - 53cm








-Diego

[diegom6]

Seating on weight's car and I think the rear could be bottoming out








On front

[atomic]

Could some of this be a result in using the e36 front struts, causing your wheel to be placed further back in the front wheel well??

Just throwing that out there. I have heard of this set up causing that front wheel placement issue, but have not heard of any problems nor fixes for that either. I went 5 lug, but with e30 m3 parts so I knew it would be correct.

[diegom6]

To give better caster(move the tire front) I could use the spindles of the E36 M3, but I'm using the regular e36 spindles, looks like the M3 units has more angle for increase caster from what I have heared from other mebers that did this conversion. other option it's treehouse bushing arms modded.

But the caster thing it's not the issue, trust me, it's about suspension travel/stiffnes.

I just made 1cm lifted in th back and almost 3/4 of centimeter of lift in the front, to see if I can get some more shock travl before start bottoming out.

[Mossman]

I just got done with my 5 lug setup and I love it on the highway.
I know you're trying your best with the english and usually I understand what you're getting at 100% and appreciate your posts, but this time it's kind of a "feel" thing and it's hard to completely understand what your problem is.

First of all, I don't think you want the konis on full stiff. Try running them on full soft, and if you are getting bounce or floaty feeling stiffen them one click til that goes away. Especially in back. I'm running E36 m3 konis front and rear, and with the rears in the middle and e30 m3 springs which aren't very stiff my rear end feels weird. It's like the koni is pulling the rear end up after hitting a bump too hard, like my booty is poppin...lol. Anyhow, I think konis on full stiff may be too much dampening and I'd look there first.

I am running e36 m3 konis in front with redrilled shock towers for offset e36 m3 strut hats, and e30 m3 offset control arm bushings. Car did drive kind of scary with lots of bump steer til I got a proper alignment done. Didn't get a print out with camber and caster so I'll be going back soon.

Good luck diego.
-Sam

[diegom6]

I just got done with my 5 lug setup and I love it on the highway.
I know you're trying your best with the english and usually I understand what you're getting at 100% and appreciate your posts, but this time it's kind of a "feel" thing and it's hard to completely understand what your problem is.

First of all, I don't think you want the konis on full stiff. Try running them on full soft, and if you are getting bounce or floaty feeling stiffen them one click til that goes away. Especially in back. I'm running E36 m3 konis front and rear, and with the rears in the middle and e30 m3 springs which aren't very stiff my rear end feels weird. It's like the koni is pulling the rear end up after hitting a bump too hard, like my booty is poppin...lol. Anyhow, I think konis on full stiff may be too much dampening and I'd look there first.

I am running e36 m3 konis in front with redrilled shock towers for offset e36 m3 strut hats, and e30 m3 offset control arm bushings. Car did drive kind of scary with lots of bump steer til I got a proper alignment done. Didn't get a print out with camber and caster so I'll be going back soon.

Good luck diego.
-Sam

Hi Sam,

thanks for the input..I had the rear konis in the soft side,I finished adjusting it all the way but it didn't make much difference, however what you just said, it's what it's happening to me , too much dampening, but not that much like when you see a car in the irregular road just driving away with a hella stiff suspension and the car it's dampening/bouncing, I mean copying all the irregular road and makes little jumps...that's not my case, but at high speeds in the highway where isn't dead flat, sometimes I will feel like it's bottoming out.

I have to tes tmy car on the highway with the lifted suspension yet, I will report later how it went.

[Mossman]

hope it helps at least a little bit so you know you're moving in the right direction. Do you have access to any other springs to try in back? Also are you sure you're adjusting the konis properly if they're the collapse fully and turn type? How much different did it act over small bumps with them on full soft. If it doesn't bounce with those stiff e36 coilovers on full soft i'd be pretty suprised.

[Mossman]

also I don't think e36 m3 spindles change caster. Have never looked at the two next to each other but I'm pretty sure they're the same.