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      10-29-2009, 06:44 PM   #1
leeor
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Would it be weird to go: Front RD, Rear Eibach??

I was wondering if its normal to do the front springs RD sport and the rear eibach?

lol, dont ask why... just curious if thats weird?

Will the ride be stiff or what? bc i know eibach are soft, rd are stiff...

does front or back cause more effect? lol wondering..... anyone know anything?

gimme feed back!
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      10-29-2009, 11:00 PM   #2
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I would think that it would throw off the balance of the car due to the different spring rates. I wouldn't recommend it.
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      10-29-2009, 11:15 PM   #3
leeor
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thank you, first reply. lets here what else
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      10-30-2009, 12:06 AM   #4
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Quote:
Originally Posted by leeor View Post
thank you, first reply. lets here what else
Your car will look "jacked up" as the RD Sport springs in the front will drop the car 1.25", which will look totally out of proportion to the 0.6" drop of the rear Eibach springs. The rake of the car will look weird. (ass end in the air, and front slammed low)

The progressive spring rate difference between the two brands, will also make the car seem like it has a nervous twitch.

This is a very, very, very, VERY bad idea.
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      10-30-2009, 12:30 AM   #5
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lol, i never checked the RD drop...however i know its way lower.

my friend told me it was the same in the rear and i forgot what the drop was but ur right, it is .6....

what do you mean it'll look like its twitching?
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      10-30-2009, 12:44 AM   #6
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Quote:
Originally Posted by leeor View Post
lol, i never checked the RD drop...however i know its way lower.

my friend told me it was the same in the rear and i forgot what the drop was but ur right, it is .6....

what do you mean it'll look like its twitching?

I mean the RD Sport's progressive spring rate in the front will be much firmer (stiffer) than the softer Eibach springs in the rear.

That will hurt the overall balance & handling characteristics of the car.

This is exactly why all lowering springs are engineered and sold in matched sets(front and rear 4-spring kits), instead of an assortment of 'mix-n-match' pieces.
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      10-30-2009, 05:58 AM   #7
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Quote:
Originally Posted by leeor View Post
lol, i never checked...
That's the real reason that it is a very bad idea.
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      10-30-2009, 08:13 AM   #8
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Quote:
Originally Posted by Lemans_Blue_M View Post
I mean the RD Sport's progressive spring rate in the front will be much firmer (stiffer) than the softer Eibach springs in the rear.

That will hurt the overall balance & handling characteristics of the car.

This is exactly why all lowering springs are engineered and sold in matched sets(front and rear 4-spring kits), instead of an assortment of 'mix-n-match' pieces.
Just playing devil's advocate here, but:

If you know what you are doing, and have a specific goal in mind, I don't have a problem mixing and matching. Spring retailers create a set-up based on what they think the average buyer will like. You may not be the average buyer.

I personally like a very stiff front end and a soft rear end (no comments on that please). When I ordered my springs from Ground-Control for the e46, I was able to set them up to my preferences.

However, if you don't know what you are doing, you can end up with a very strange handling car.
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      10-30-2009, 10:55 AM   #9
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Quote:
Originally Posted by Radiation Joe View Post
Just playing devil's advocate here, but:

If you know what you are doing, and have a specific goal in mind, I don't have a problem mixing and matching. Spring retailers create a set-up based on what they think the average buyer will like. You may not be the average buyer.

I personally like a very stiff front end and a soft rear end (no comments on that please). When I ordered my springs from Ground-Control for the e46, I was able to set them up to my preferences.

However, if you don't know what you are doing, you can end up with a very strange handling car.
+1

This is a great point, but as Joe mentions, it's extremely important to know how different spring rates are going to affect the handling bias of your car. Your safest bet is to go with the package deal.
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      10-30-2009, 10:56 AM   #10
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      10-30-2009, 11:04 AM   #11
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I wish these companies would publish their spring rates. I really would like to use H&R in front and RD in rear, but without knowing the spring rates I won't risk wasting the money.
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      10-30-2009, 12:15 PM   #12
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As a layman, I would ask: How many people have done this? Not just here but with other cars? I have seached some sites and the answer is none.

There is a reason why- its been explained by Lemans...
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      10-30-2009, 12:56 PM   #13
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A completely different thought would be to contact Ground Control as I'm pretty sure they have a "coilover conversion" kit for our cars. Then you can pick whatever ride height and spring rate you want.

BC
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      10-30-2009, 01:14 PM   #14
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haha yea the drop difference is way far apart from front and back, I know RD is over 1 inch, and the rear we got confused with eibachs and here i came to see that its .6 for the rear drop. But i was just curious to see if such a thing was reasonable to do so or even possible.

Thanks for all your feedback
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      11-05-2009, 01:49 PM   #15
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Quote:
Originally Posted by Radiation Joe View Post
Just playing devil's advocate here, but:

If you know what you are doing, and have a specific goal in mind, I don't have a problem mixing and matching. Spring retailers create a set-up based on what they think the average buyer will like. You may not be the average buyer.
Yes, but with GC you probably had a linear spring. The RD, Eibach, Dinan, stock are more than likely progressive rates, so it's not going to be the same effect.

Most track guys will run vastly different spring rates, but not on progressive street springs.

Quote:
I personally like a very stiff front end and a soft rear end (no comments on that please).


Quote:
However, if you don't know what you are doing, you can end up with a very strange handling car.
yes.. tons of hopless understeer.
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      11-05-2009, 04:24 PM   #16
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might as well just cut ur stock springs.
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      11-06-2009, 01:41 AM   #17
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I know a few people here in Europe who can make any set lowering springs for you.
But for BMW's he advised, front not lower then 35mm and rear not lower then 25mm.

They made a set for me 10% stiffer then OEM and the following lowering :

Front 28mm (1.10")
Rear 16mm (0.63")

With this set the front and rear gap is almost the same, maybe a difference of 1 or 2mm.

It is a little expensive but it is custom build.
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