E34 Track Width

[theBMWbeast]

I’ll preference this by saying, every other bolt on suspension upgrade you can do, I have. Every suspension component that doesn’t have an upgraded replacement, is brand new Lemforder. I also have competent tires on the car, on 18” wheels. The brakes are upgraded and stop with authority. So with that out of the way, I’m here to address the last bit of noticeable, theoretical improvement.
I had tried, with great naivety, to fit e31 upper control arms on my e34. Afterwards I wondered why my suspension was wonky, surely the newfound negative camber couldn’t be the issue (lol). Further research indicates that a similar phenomenon happens in the rear if one were to fit e32 trailing arms in replacement of the e34 arms. This would result in a widened stance, while maintaining proper suspension geometry, compared to achieving the same with wheel spacers. Atleast to my understanding, that is.
So my question is multifaceted. If I were to fit e31/e32 upper control arms, could I correct the negative camber with adjustable camber plates? If I fit e32 rear trailing arms, would the wheels still fit within the wheel wells (Same question goes for the front as well, but I think the clearance problem up front is usually tire/strut housing contact. But would my turning radius be limited with the wider stance?)
Would this new widened stance make a noticeably improvement, or am I looking at diminishing returns on effort/investment here?

TL;DR I’m thinking of widening the stance of the car for better handling. Worth it or too much of a headache/ not feasible?

[theBMWbeast]

https://www.bimmerforums.com/forum/s...er-Track-Width

Before someone says search, I will add I found this thread a while back. However I know by now, someone has to have real world experience with e32 trailing arms. The front situation is semi-addressed in the above thread, although he mentions a few degrees of camber. I would be interested in getting it to factory specs...

[Hofmeister]

IIRC yea the rear stuff does mount up, but likely wont clear stock bodywork. And same on the front. You could use coilovers with camber adjustment and take off camber by pushing the struts out. The real question is how much of a gain is there really to be had from all this work. Compared to just better tires or wider wheels.

EDIT: read through the thread you posted, the one guy who posted pics of his setup. My current fitment is pretty much the same as his, and we even run the same springs. Only difference is i run 18X8.5 ET15 front wheels with 245 tires and some bumpsteer plates which pushed the strut housing outwards slightly. As it stands this barely fits and rubs going up driveways and such.

[cirrusblau]

E34 rear trailing arm part number cross-references with E32, E28 and E24. I doubt it will give you more width. I think what give the E32 more width in the rear is a wider subframe.

EDIT: Upon further Googling, I found this:



Doesn't explain though on what he did.

[theBMWbeast]

Thanks guys. Looks like the benefits could be replicated with simpler setups, and then its a question if it’s even a benefit. I wish they gave some info in that video, that is obviously exactly what I want to do. I wonder if some normal tires could fit within that space, but instead of answers we just get music to listen to

[E38740iMD]

Lmao

I like the music.............

[Hofmeister]

Thanks guys. Looks like the benefits could be replicated with simpler setups, and then its a question if it’s even a benefit. I wish they gave some info in that video, that is obviously exactly what I want to do. I wonder if some normal tires could fit within that space, but instead of answers we just get music to listen to

i mean it looks like you have most of the knowledge on this already. Its mostly into wether you find it worth it. That car has some hardcore fender work done to fit that setup. And since you seem to want performance at whatever cost id just recomend some 10.5" rears with lower offsets and 295s. Or some smaller yet still lower offset wheels. But imho having a ton of tire looks better anyways. If you have adjustable rear subframe you can also play with camber to help settle in the wheel well better.

[gderian]

E34 and E32 trailing arms are the same. But the hub on the E32 is offset 10mm each side to provide a slightly wider track. This also requires E32 brake rotors so the parking brake drum lines up.

[moroza]

Slight thread necro, but I'll add my datapoint: E34 fits E32 trailing arms and hubs with 17x8" M-Systems and 245/45R17 tires, with not much room to spare.

[theBMWbeast]

A thread back from the dead, perfect for Halloween. Still haven’t done this, wondering if my 18x 9.5” Mpars with 265/35/18 tires will clear. Might just have to try and find out.

[jawnswagg3r]

you missed a thread with an identical title. my posts are towards the end of the thread.

"i run the longer e32 upper control arms with the lower control arms in the outboard e32 holes, instead of the stock inward e34 holes. not super extreme.... but definitely a wider track. e34/32 tie rods are same P/N just have to be lengthened to fit. everything is compatible, suspension geometry is now e32 stock essentially. i run kmac camber plates. only thing i have problems with is fender clearance. lowered on vogtlands, i have severe rubbing with 17x8 et20 style 19s. 235/35/17 i think? hankooks. basically waiting on coils to really figure out fitment... looks and drives good with a healthy few degrees of camber. trying to figure out a clean way to creatively widen the front fenders..."

https://www.bimmerforums.com/forum/s...6#post29724366