Review on E30 Suspension setup

[tibbs.james 1]

Hi Guys.

I would like to post my reviews on my current suspension setup on my E30 320i.

Also read lower for questions on front camber castor.

The setup is Koni Sport rebound adjustable front and rear

( Older model yellows that do not have the external white adjustment )

325 Front and rear larger sway bars.

Ireland Engineering rear sub frame mounts and T/A bushings

Eibach progressive springs ( rate unknown ) 30mm drops.

I have never been for a ride in an H&R bilstein fitted E30 or a series car for that matter but with the eibach lowering springs and the front shocks set to 50 % hard front and back the car feels very nice on the road. The ride is slightly firm and you do feel bumps in the road but its still rides very well and is not harsh in any way.

NO REAR SWAYBAR

i noticed more body roll and unpredictable oversteer with no sign of understeer.

REAR BAR FITTED

Traction was a lot better body roll was gone around an average to sharp corner there was no real sign of understeer.

Around a tight roundabout there was fairly apparant understeer and the front tires making a fair amount of noise.

I think the car was a lot better with a rear sway bar, currently fitted with a single spinner and spinning up a wheel by accident is almost totally gone.

Front Camber,Castor.

What are the options here for front camber castor. currentlty i have factory strut tops and factory rubber bushings.

Bushings need replaced ASAP, Could somebody please explain the advantage over the offest "m3" type bushing and why people use it ?

I would also like to know if increasing my front camber a little with help with the hints of under steer i have been getting, 30mm lowered to give an idea of ride height and front camber.

Any advice on what type and brand of bushing to go for would be great.

Cheers

James

Edited December 7, 2008 by Jimmy

[JiB 0]

Have done offset castor bushes as well as camber/castor strut tops. The more castor, the better my car drove....to the point I want to cut up my strut tops so I can have even more castor.

The offset LCA bushes are in the top ten mods imho. I used the el cheapo noltec ones, haven't had a problem with them.

I liked the excessive toe/camber setup in the rear when I had the car's chassis 90-100mm off the ground. Felt like a go-kart. Probably terrible on tyres. The front camber really doesn't seem to be affected much by lowering tbh.

This is only my 2c. I'm sure people with more suspension knowledge will chime in.

[tibbs.james 1]

Thanks JIB, that's quite helpful.

My rear camber isn't excessive but i am getting mild inside edge wear on the rear tires, however it took 2 years of having it lowered to get that far so im happy with tire wear at the back.

Chch BMW are selling me a pair of genuine BMW E30 M3 eccentric front bushings for around $96+gst, if they are good enough for a M3 they will work fine on the E30.

Does the 1/2 degree camber change on the offset tops really make a difference or are adjustable ones required to make enough difference ?

[|ncary 0]

To answer your question about the offset bushings in the control arm lolliepops: They push the front wheel out and furthur forward, both really good things. You install them with the holes in the bushings towards the inside of the car.

For the past year I've been doing hours and hours of suspension research for E30's. Soon I'll be purchasing it. If anyone knows Stucks car, from bimmerforums and e30tech, that'll be very similar to what I'm getting. No more rubber anywhere in the suspension yay!

[CamB 48]

Does the 1/2 degree camber change on the offset tops really make a difference or are adjustable ones required to make enough difference ?

If you are DIY (ie don't pay labour), then you could just see what the camber is after getting the offset castor bushings, and if its too low get the offset top mounts.

The M3 offset castor bushes are good - I have them on my E36 M3 (and mine the late E36 M3 Evo with longer control arms). I have monster castor, and it feels great.

Edited December 8, 2008 by CamB

[tibbs.james 1]

Thanks for comments Incary & CamB,

Yes I am DIY so I i might measure it and see what it is, might have to make do for a while.

Fitting the Offset Bushings is no worries, but what about wheel alignment, is there specific requirements that can further improve handling once these are fitted ?

If i take it to a normal wheel alignment place is there any possible way they can muck it up, or i could I provide them with some specifications to use ?

My issue is I do not work in a rural town and only have access to basic tire shop wheel alignment facilities.

What would be considered too low for front camber?

Edited December 8, 2008 by Jimmy

[CamB 48]

Certainly less than 1 deg is probably a bit low for spirited driving. The E30 Series race cars are limited to a max of 2 deg and they handle pretty damn well (although some guys want more camber). Either way, it isn't adjustable - it is what it is.

I dunno on toe - whatever the factory recommends. Its the only thing you can adjust anyway!

[Mike 1]

To answer your question about the offset bushings in the control arm lolliepops: They push the front wheel out and furthur forward, both really good things.

huh? pretty sure they only move it forward, track wont change, not by a noticable amount anyway.

Jimmy, quick a google for castor will explain it pretty well, generally you get greater straight line stability at the expense of more steering effort. dynamic camber is also increased (more camber when the wheel is turned).

My car is 60mm lower at the front and camber is at 1.6 degrees, not an issue. last wheel alingment my rear camber was 2 degrees and the wear is still too much on the inside, probably due to driving in chch city with no corners to wear evenly. Just go with factory settings for toe.

Plenty of options for bushings, you cant go wrong with OEM M3, but other options are powerflex, treehouse racing, or AKG.

Good to see someone asking how the modifications will affect their car.

edit: wheel alignment specs should all be on their computer, castor will be out of spec with the M3 bushings, just explain to them before why it is. as long as its the same both sides its all good.

Edited December 8, 2008 by Mike

[JiB 0]

For toe settings, I was told 1deg total toe front- .5 each aids with turn in. But this was settings off a series car with M3 offset bushes top and lower.

Factory is 2deg toe IIRC.

Again the above is my 2c, which is being applied to my racecar so may not be suitable for road use.

[bravo 35]

My car ha 40mm lowering.

My alignment is almost identical on both sides and I have 2.5 degrees neg camber on front, 3 deg neg on rear, and factory toe. I have setback on the front which is right on max so something s not perfectly straight, but not out by enough to cause problems. I can't remember castor, but it is not within factory spec.

Started to wander a bit mid corner with bumpsteer the other day and got an alignment - toe was out and problem is now solved.

Always wondered about offset bushes but handles very well as it is so never bothered.

[CamB 48]

Bravo - you should try the bushes. JiB's car felt fantastic after putting them in when it still had more or less standard suspension. It improved turn-in heaps.

[tibbs.james 1]

For toe settings, I was told 1deg total toe front- .5 each aids with turn in. But this was settings off a series car with M3 offset bushes top and lower.

Factory is 2deg toe IIRC.

Again the above is my 2c, which is being applied to my racecar so may not be suitable for road use.

Thanks for the Numbers JIB

I will fit them up and see what the alignment machine says. As the shop will have the toe on their computer i can confirm if you remembered the correct factory spec.

Bravo - you should try the bushes. JiB's car felt fantastic after putting them in when it still had more or less standard suspension. It improved turn-in heaps.

CamB

What did the car feel like before it had a new wheel alignment when the new bushings were fitted. Definitely a big improvement to be had after a wheel alignment?

Reason I ask was mine was done a month ago not realizing my lower arms and bushings were stuffed.

I Do know i need to have one done, but how soon is another question.

Edited December 9, 2008 by Jimmy

[|ncary 0]

huh? pretty sure they only move it forward, track wont change, not by a noticable amount anyway.

f**ked up sorry. Was thinking of what I will be doing to my setup..

[CamB 48]

The car hadn't been aligned before, so who knows. The big difference you feel is how the steering starts to weight up as you turn and the dynamic camber helps a lot.

You do need to get it aligned afterwards - moving the wheel forward does mess up the toe.

Edited December 9, 2008 by CamB

[JiB 0]

The car hadn't been aligned before, so who knows. The big difference you feel is how the steering starts to weight up as you turn and the dynamic camber helps a lot.

You do need to get it aligned afterwards - moving the wheel forward does mess up the toe.

I think we put them in not long after I bought the car....IIRC the previous owner said the car had just been aligned with the new tyres for wof.

But to be honest, the "new tyres" were snow tyres, so it may have been a cheap/rough spec alignment..

CamB and I drove it immediately after we got them in, so pre alignment and the turn in was instantly improved. The car was then aligned as close to factory spec as possible.

I drove it pre and post alignment after installing the bushes....and the turn in was dulled post alignment to be honest. I have the alignment sheet here somewhere, will dig it out.

Maybe it might be an idea to get M3 bushes and strut tops then use a combination of standard and E30M3 alignment settings? (I'm thinking of using E30M3 alignment specs - in theory my car now has roughly the same castor and camber amount as M3.)

[Mike 1]

Maybe it might be an idea to get M3 bushes and strut tops then use a combination of standard and E30M3 alignment settings? (I'm thinking of using E30M3 alignment specs - in theory my car now has roughly the same castor and camber amount as M3.)

Thats what i was thinking of doing, as I'm due for alignment also. lower ride height will also be a better match for most of our cars

[tibbs.james 1]

Thats what i was thinking of doing, as I'm due for alignment also. lower ride height will also be a better match for most of our cars

If somebody Can provide the M3 alignment specs I would be willing to try these out and report back.

My M3 bushings are here for me to install,I will book alignment in for monday if somebody can probvide some specs.