Question on coilover spring rates

[DanPromote]

May I know if anyone is using coilovers here and what is the recommended spring rate for the front and rear? I'll be upgrading the stock suspension to coilovers as it seems to be much better value/performance over lowering springs, about RM2,200 for a new set and it's lifetime servicible.

 

[M30revival]

Without knowing what model you drive, it is just impossible to give you an indication of what springs rate for your car.

If you are going for coilover, the installer should weight your car (if they have such facilities) and then recommend the right springs rate for you. That's what they should do when they say they can 'customized' the coilover for your car. If they asked you for the recommended springs rate to fit your car, you should get a 2nd opinion from other installer.

 

[DanPromote]

sorry I forgot to mention it's a 318i(m) E36

 

[Crymson]

you should update your profile, listing the series and model you drive

 

[teejay]

the spring rate will also depend on the type of performance you want out of your car
you will need the installer to match your absorber rebound rate, as it has a significant factor on the dampening rate
if you are going to use coilovers, then suggest you get aftermarket and adjustable rate, possibly for the damening since it will be cheaper and easier to adjust spring dampening rates then absorber rebound rates

 

[DanPromote]

Crymson, just did that thanks.

tejay, I'm going for aftermarket coilovers. They're only adjustable hi-low but spring and damper rates can be customised before collection. They do have a stock setting for 318(i) but I'm wondering if that is ok or should I change it.

 

[fabianyee]

which brand of coilovers are u going for???

 

[DanPromote]

RG, it's a German based brand which links to Bilstein and H&R. They have a local factory here that's why Im choosing it over imported brands, at least if there is anything wrong I can go back and re-do the setting until I'm satisfied.

 

[fabianyee]

RG??? hahahah... RG is the initial for Rudy G-something... He was the same guy who developed the coilovers for Hotbits and then went over to APM and started RG... German based brand? is that how they market it? Last I know, Rudy is back in Germany. so it's partly true that RG is 'German Based'...
And from what I know, Hot bit's coilovers are better now after a Netherland chap took over. Better R&D compared to Rudy's time.
I don't know Rudy or even Speedworks, but I know someone who is fabricating some of the bits and pieces for the coilovers. I've seen the quality, nice

 

[teejay]

Originally posted by DanPromote@Nov 2 2005, 03:41 PM
Crymson, just did that thanks.

tejay, I'm going for aftermarket coilovers. They're only adjustable hi-low but spring and damper rates can be customised before collection. They do have a stock setting for 318(i) but I'm wondering if that is ok or should I change it.

suggestions

1. go for standard rates with springs adjusted for medium height
2. when set to low spring rates increases, dampening rates are shorten
3. when set to high, you get max dampening, thus more comfort

or
1. set for higher rates when springs at its lowest
2. then comfort can be tuned as you adjust the heights higher

on a long term, what other upgrades are you planning?
larger antiroll bars? PU bushes, adjustable camber and castor angles?

the other most forgotten factor, how big are your wheels/rims combo?

 

[DanPromote]

Yea fabian Rudy was formerly the head designer for Bilstein & H&R as well, I'm taking the chance to test out RGs because the co. that I work for is one of their resellers (also due to the discounts I'm getting). They cost slightly over Eibach springs so it makes sense for me to go for coilover than just springs alone. There're not many BMW coilovers done so I'm sorta being the guinea pig. Just hope that it works out well!

Teejay, I'm planning to get whiteline anti roll bar, any idea where to get them? I was recommened to get the biggest that I can find. Most probably I'll be going for 17in lightweight rims so I hope there won't be much power loss. Also removing the catalytic converter and re-routing the exhaust to 2inch straight system (with silencer) to gain back some power loss due to the bigger rims.

 

[teejay]

Originally posted by DanPromote@Nov 4 2005, 02:32 AM
Yea fabian Rudy was formerly the head designer for Bilstein & H&R as well, I'm taking the chance to test out RGs because the co. that I work for is one of their resellers (also due to the discounts I'm getting). They cost slightly over Eibach springs so it makes sense for me to go for coilover than just springs alone. There're not many BMW coilovers done so I'm sorta being the guinea pig. Just hope that it works out well!

Teejay, I'm planning to get whiteline anti roll bar, any idea where to get them? I was recommened to get the biggest that I can find. Most probably I'll be going for 17in lightweight rims so I hope there won't be much power loss. Also removing the catalytic converter and re-routing the exhaust to 2inch straight system (with silencer) to gain back some power loss due to the bigger rims.

absolutely no idea on the bars


but word of advise is to check out the rubbers that come with them, if you have the option of getting PU bushes for the bars, do get them, as aftermarket rubber bushes are difficult to come by, especially older model cars......known a paricular guy that had extra large ACS bars but couldn't get replacement bushes.....and can't get it from manufacturer too.......

 

[M30revival]

I was doing some research of my own and found this

http://www.autotrade.com.my/forum/allposts...n+manufacturers

Of course, YMMV since you are working for one of their reseller.

 

[DanPromote]

thanks teejay, will certainly keep that in mind!

M30, that was back in 2004 so far the new models are in much better shape anyway if anything goes wrong they'll definately be hearing from me. Some recent user reviews this year (just hope that it works just as well for BMWs):- http://www.protongtiforums.com/forum//foru...=812&PN=1&TPN=1

I've been told that the e36 rear suspension design is quite different so it's not adjustable, only the front is, is this true?

 

[fabianyee]

u can get whiteline from Pentagon... Saw their ad in Hypertune sometime back. Or Mr Tee in Paramount can source for u too...

Or order online from http://www.whiteline.com.au/

however, be aware that when u're using thicker anti-roll bar for the rear, there's a tendency of the mounting points getting torn off. That's the reason why the Ireland Engineering antiroll bar kit for the E30 has the Aluminum block as bracket for the rear.

 

[M30revival]

Originally posted by DanPromote@Nov 4 2005, 10:22 AM
I've been told that the e36 rear suspension design is quite different so it's not adjustable, only the front is, is this true?

The E36 has independent rear suspension so it is not cost efficient to do adjustable coilover. Of course if your installer has the right tool, he might be able to customized one for you but you'll need to use very small coil springs since there is very little gap for the rear strut to accommodate the springs.

 

[DanPromote]

How would you compare eibach + stock springs vs. coilovers? In terms of performance and comfort level.

Just went to Klang today and bought myself a set of Eibachs & 17in AC replica rims (after considering I prefer comfort over outright performance). Found out the following during installation :-

1) Both front absorbers are stock BMW abs, rear are bilstein
2) Front left absorber is worn, and the rear left has oil leak

So in other words I will need to replace 4 absorbers. Will it be worthwhile changing the 4 absorbers or sell off my new eibach & get coilovers?

 

[M30revival]

Originally posted by DanPromote@Nov 5 2005, 08:22 PM
How would you compare eibach + stock springs vs. coilovers? In terms of performance and comfort level.

Just went to Klang today and bought myself a set of Eibachs & 17in AC replica rims (after considering I prefer comfort over outright performance). Found out the following during installation :-

1) Both front absorbers are stock BMW abs, rear are bilstein
2) Front left absorber is worn, and the rear left has oil leak

So in other words I will need to replace 4 absorbers. Will it be worthwhile changing the 4 absorbers or sell off my new eibach & get coilovers?

Hmm, if you are going to replace the absorbers and springs, might as well go for the coilover. Your installer should be able to customize a set that has the performance characteristics that you want and still give you 'reasonable' comfort level (you can't have the best of both world). At least the 'adjustable' nature of the coilover (only the front, remember) allow you to adjust the ride height. Fix springs like Eibach will lower your car (depends on the model).

Why would you buy a new set of Eibach springs when you are not sure of the conditions of your absorbers? Did you get Eibach Prokit or Eibach Sportline? They have different lowered height.

 

[DanPromote]

M30, it was sort of an impulse buy and I didn't know that the absorbers were worn before I took it out. It's the prokit.

Before I went to Klang I visited Mr Tee in Paramount and acc. to his feedback there were a lot of customer regret after installing coilovers (didn't ask him what brands they used), mostly complainted about the hard and uncomfortable ride, so that also persuaded me to get the Eibachs first.

 

[teejay]

hard and uncomfortable, i believe is due to mismatch of the rates

it maybe as if the absorbers are not working at all

alot of factors needed to be taken into account, rear weight, vehicle distribution weight, additional stuff, e.g. antiroll bars, strut bars etc,etc, before a proper setup can be tailor made