Camber correction.

[jaistanley]

I have a 1990 318is and have just installed offset poly front bushes, new rear top mounts, koni rear shocks and H&R springs.

The car drives a million times better than before but the extra camber is noticable. As good as this may be for handling or road holding, wheels and tyres are next on my list and i want to get sensible milage out of them!

What do I need to do to adjust the camber to either standard or sensible ammounts of camber on both the front and rear?

I understand different top mounts might be able to help. If so which ones and what are the part numbers? Also, is it possible to use M3 EVO top mounts for increased castor? If so, is this reccomended?

Many thanks in advance.

Jai Stanley

[Dan318-is]

wenever u lower ur car, regardless of what components are used and what model the car is, (this includes models which are not bmw also) the steering angles set by the manufacturer, e.g. camber, castor, and king pin inclination) are all changed. Incorrectly adjusted angles can lead to tyre wear and dangerous sterring characteristics such as bump steer. The best way mate is to go to a garage and have them fiddle with all your angles so that they are reset, although i believe castor is usually unadjustable unless special plates are fitted.

[jaistanley]

I understand chassis dynamics. I'm after the practicle sollution guys on this zone have gone for. I could go buy or make camber adjusting top mounts or even as far as a re-jigged rear beam but just want to buy some bolt on bits. My car is a daily driver and I'm just trying to make the best out of it in a cost effective manner.

Cheers though.

[Dan318-is]

if its just for a daily drive an yourjsut using it as a fast road car i would just get the angles reset as the likeleness of you needing to adjust the angles is rare. Track day use however, would mean this is the premium choice


glad i can help

[gareth]

unless you're really low, the front will probably be fine. more negative camber on the front will help turn-in.

the rear is not so good though and will eat tyres. offet bushes are available (not sure where from though) . these will tilt the wishbones back to nearer the correct angle.

[Demlotcrew]

^ BMW Ԛ£25 per side.

A

[gareth]

cooool!

i may have to get some myself.

does anyone make any polyurethane ones? i have polyurethan M3 wishbone bushes ready to fit too so i may as well go the whole hog...

[jaistanley]

dont kmac make offset poly ones for Ԛ£80

Look at this: http://e30m3performance.com/tech_articl ... c_bush.htm

Really good site.

Jai

[astondg]

I have the K-Mac polyurethane ones. I can't tell you much about them though because I haven't had them in for long and my car wasn't low enough to have camber problems. I use it for racing too so the little bit of extra camber I had was good, I think it still has the same amount with the bushes installed. I mostly wanted the front ones to get more negative camber at the front and thought I'd get the rears at the same time. Seem to be ok though.

K-Mac now has an option for another sort above the normal polyurethane ones, at least for the front anyway, but I sent them an e-mail and they said that they are only really for race cars. They though that for my cars use, normal road car with about 10 autocross events and 10 to 15 track days a year, the normal polyurethane are best.

Aston

[karlp]

You have a couple of options.

Polyflex make some eccentric rear bushes (BMW also) that you can use to adjust the rear camber. However you need to know what the camber is before adjustment and then install the new bushes at the correct orientation to achieve what you want. If you get it wrong then remove these bushes and start again.

KMac make some adjustable bushes that can be set up on the car. AS long as they are installed correctly and tightened to the correct torque then should be ok. There has been some reports of them comming loose but this can be prevented by tack welding the nut once adjustment is correct. These you can get from Moseley Motorsport.

Fronts - you can get adjustable ones from Moseley also- but they are expensive.

Karl

[Simon13]

if u have h&r springs yes? then thats 35mm drop me thinks.

My car has these springs and the negative camber is no worse really on the rear. Is your subframe bushes shagged? this will not help the situation as when they collapse the back end drops about 10mm so more neggy camber!

[jaistanley]

To be honest, the camber on mine isn't exsessive, especially after seeing Karans the other day (that seems immense fun to drive but eats tyres apparently).

I'm more interested in getting the 'right' camber and toe for everyday driving and grip/handling. Has anyone experimented with this?

The most developed BMW ever made this semi trailing arm is the M3 touring cars, and recently the MCoupé. The race car has a few differences apparently, a sweep angle of 12 degrees instead of the usual 15 on the subframe for instance. Does anyone know the camber and toe of a standard MCoupé?

I'm thinking of adapting a subframe to have a 12 degree sweep angle and either 'pre-programmed' or adjustable camber. One thing I need to find out is the effect sweep angle will have on the standard swingarms. The race cars may have had different geometry so the toe isn't affected

Here's a very good link I found:

http://e30m3performance.com/tech_articl ... /index.htm

Any input'd be cool...

Jai

[Demlotcrew]

ITs no good just adjusting the sweep angle, you will also then need to adjust the CG of the outer arms on the rear.

A

[jaistanley]

Yea, thought so.. Was thinking about it a bit more after I posted...

Still, I might still make an adjustable camber/toe subframe.

Jai

[karlp]

No disrespect intended but I think you are living in fairy land.

You have a 318 is- nothing special - and thinking about building trailing arms. If it is a university project then great, I see the point but for the general road then pointless.

The biggest issue is not the trailing arm BUT once you start messing with the construction of the chassis /suspension then insurance become a big problem.
Unless of course you do not intend telling them - in which case you ain't covered.

I have a race car - much easier to use available bushes which do the job just as well.

Karl

[Demlotcrew]

Yea, thought so.. Was thinking about it a bit more after I posted...

Still, I might still make an adjustable camber/toe subframe.

Jai

For the rear i think its a good idea. How practical it will be with the British climate is anyoneÔš's guess. I use the eccentric bushes from BMW and they work well. I have yet to try them out on the track.

But i think its a good plan.

A

[jmc330i]

You might already do this, but I will say it anyway cause it may save you some money.
If the rear camber isnt excessive, then just keep checking the tyres every couple of months.
When the inner side of the tyres have worn down some, have the tyres changed so they are on the opposite wheel. The inner side becomes the outer etc, and you will then be running on the relatively unworn side of the tyre.

The camber on mine isnt huge, but I forgot to do this and wasted 2 tyres in about 9 months. The outer side still had about 3-4mm, the inner was illegal. The next set of tyres lasted me nearly twice as long cause I remembered to have them swapped.

[Karan]

yeh id swap fronts with rears to be honest....... as the fronts wear the outsides and the rears the inside if u drove oit hard...

and Karl.... Jai isnt living in dreamland. LOL he knows what he's on about!

the e30 rear trailing arm issue is a problem in low grip and mid corner bump situations,,,, if u have high camber like on my car, rear grip suffers in the wet as the tyres never fold enough to justify the camber it runs, however in the dry it is planted!!! mid corner bumps also affect it heavily

Karan

[karlp]

I agree with the concept of improving the rear camber but according to the above posts Jai wants a simple cheap bolt on kit which is a much simpler and cost effective method than making suspension components.

Unless the car has been dropped by about 80 - 100mm I cannot see the point in making trailing arms.

It all comes down to cost vs benefit and the most cost effective benefit in this case is adjustable trailing arm bushes.

If the construction is just for the sake of something to do and for the pride of making something that no one else has then I applaud the efforts.

In which case look at www.s14.net - there are some good ideas on there and pics.

Karl

[gareth]

who sells the Polyflex bushes and how much are they? the bmw ones seem a bit expensive!

[jaistanley]

I'm not living in dream land! Sometimes my plans are a bit bigger than the time I have but they're always based on reasonable engineering principles.

It really wouldn't be hard to knock up a simple camber adjustable sub-frame. The 'tangs' that support the semi-trailing arms can be made with a big enough hole to accept a high tensile eccentric bolt such that demon tweaks sell. To allow adjustment , the bolt's head would be 'wedged' between two welded on bits of steel. When turned it'd rotate the shaft thus moving the trailing arms. God that was hard to describe and possibly made no sense!!!

http://e30m3performance.com/installs/in ... /index.htm

I have acces to blasting kit, paint, grinders (grrr) and a decent high current mig. Reccon I'd make an OK job and if I balls it up, I wont put it on! If its the tits, I could make a few for helpful zone types.

I'm not just after a bolt on sollution. If you guys reccon the BMW or poly eccentric bushes are bset, i'll take your word. You guys have been behind the wheel of more E30's than I have!

Making a frame with a different sweep angle is way out of scope though. Would have to make up new trailing arms and to be honest, until I'm trying to shave off tenths from my nurbergring time...I'll pass!

Anyone have an oppinion what'd be best for my car:

318is. E30 M3 running gear, 15" BBS 205-55-15 (5 stud), H&R springs, Koni adjustable rears, standard M3 front dampers.

Thanks guys.

Jai

[karlp]

I understand chassis dynamics. I'm after the practicle sollution guys on this zone have gone for. I could go buy or make camber adjusting top mounts or even as far as a re-jigged rear beam but just want to buy some bolt on bits. My car is a daily driver and I'm just trying to make the best out of it in a cost effective manner.

Cheers though.

So if you are not after a bolt on kit - what does the above quote refer to.

Karl

[jaistanley]

T1ts. It's one of those posts that goes on and you forget what you were getting at!!! Last night was bit of a PWS (post whilst stoned)

OK.. So what are the best bolt on bits? The BMW offset bushes (how much by the way) the K-mac or should I give making my own beam a go so I can use 'normal' bushes?

Cheers...

Jai

[Simon13]

u can get offset special front top mounts from BMW they are over Ԛ£100 each though anf not worth it for what u are doing!

[Jimbob]

Anyone know why my -60 H&R springs at the FRONT bow the wheels right in..shagged track rod ends?

[Simon13]

no just negative camber jimbob. Mines the same on 35mm h&r's

[Demlotcrew]

First off i would try and match all the dampers.

A