# Koni Sportkit springs vs Eibach Pro-Kit



## lucky (May 2, 2005)

I haven't been able to find out much about the springs in the Koni 1130 Sportkit. Does anyone know how they compare to the Eibach's, in terms of ride quality and lowering? Does Koni actually manufacture them, or are they outsourced?
Thanks for any info.


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## jpr (Aug 12, 2005)

There might be some differences on the E46 vice the E36, but I believe the Koni springs are made by Vogtland. As for spring rates all are about 10% to 15% stiffer than sport stock, with the H&R sport will be stiffest, Eibach the softest, and Koni/Vogtland somewhere betwixt. But the differences will be relatively small and they will be closer to each other than to the OE springs. The OE springs, incidentally, I believe are made by Eibach.


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## pww71 (Jun 1, 2005)

*Koni is a subsidiary of ITT Industries Inc. NY, USA*

Koni is a Dutch company, I grew up close to their facility in Oud-Beijerland, Netherlands.

http://www.koni.com/home_menu/_company/company.html


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## lucky (May 2, 2005)

Despite the lack of feedback out there, I think I'll give them a try. I've come across some good comments for Vogtland on European posts. And if Koni likes 'em they're probably alright, so what the heck.
Thanks for the replies jpr & pww71


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## franka (Jan 23, 2006)

Eibachs are softer than factory sport.


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## RottieLOVE (Sep 13, 2006)

*H&r*

Jpr mentioned H&R springs ... I put on my E46 325i H&R Cup-Kit-Sport-Suspension-Kit and I'm very satisfied with the ride ... car lowered with 35mm front and 20 mm rear springs looks like that (http://www.bimmerfest.com/forums/showpost.php?p=1917122&postcount=22). You can also go extreme with combination 55/35 mm and if I remember correctly even go crazy with 70/50mm


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## franka (Jan 23, 2006)

Konis are softer than factory sport struts in compression and you can't adjust them any stiffer. They are only adjustable in extension. Konis are good for a soft ride and for boulevard queens.

Bilsteins are a better performance shock. 

I've had both on my car.


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## jpr (Aug 12, 2005)

franka said:


> Eibachs are softer than factory sport.


It might vary by application, but in regards to the E46 and E36, I don't believe that is correct. Actual data is certainly hard to come by, but from measurements of the OEM sport springs I removed from my car compared to data from the TUV cert of the Eibach Pro-kit, the Eibach springs
* in the front the prokit springs have the same max OD, but have a slightly larger wire diameter 
* in the rear, wire diameter is also slightly larger, and the max OD is slightly smaller
While the information is complete enough to be truly definitive, the implication is that the spring rates would be higher with those changes.



franka said:


> Konis are softer than factory sport struts in compression and you can't adjust them any stiffer. They are only adjustable in extension. Konis are good for a soft ride and for boulevard queens.
> 
> Bilsteins are a better performance shock.
> 
> I've had both on my car.


Again, without actual shock dyno data it's impossible to definitively compare them, but I'm not sure how accurate your generalizations are. Generally speaking though, rebound rates have a much greater impact on handling than compression rates, so even if the Koni's do have a softer compression setting than the OE Sachs or Bilstiens, you couldn't necessariliy conclude that meant lower performance. For example, I believe the main difference between the various Sachs struts used on the E46 is a change in their rebound rates rather than compression. This is an inference from the "parameter" code used by Sachs to describe their dampers. While I haven't really cracked the code, it certainly looks like their is a logical pattern.
Standard strut - SFE32X56A
Sport strut - SFE32X86A
ZHP strut - SFE32X98A
Regarding the Bilstein vs Koni debate, I think both are excellent pieces of equipment. The Bilstiens I believe are compatible with a higher range of spring rates than the Koni SA's, but consequently can be somewhat overdamped for lower spring rates. The Koni's one big advantage in comparison with the Bilstiens is their adjustability. If you enjoy tweaking and tuning your suspension, then more ways to adjust things is better than fewer.
Lastly, since I'm sure it will come up, Dinan, Ground Control, and TC Kline all use Koni dampers in their packages. However most, if not all, of these outfits also claim to use special custom valving, so it's not really possible to draw much in the way of meaningful conclusions.


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## franka (Jan 23, 2006)

Bumps that were nothing at all to worry about became a problem when I went from factory sport suspension to Eibachs and Koni's. Bamm, bamm. Bottoming suddenly became a real concern.

I put in Bilstein HDs and no more bottoming problems, plus the car became much, much more tossable.

Dinan's performance suspension and others you mentioned that do come with Konis have been specially valved like you said. 

They do that because the standard Koni is not acceptable. I think that says it all. 

Konis are good if you like soft which was what I said in a prior post but with a conservation of words.


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## jpr (Aug 12, 2005)

Makes sense - monotube dampers by design will typically have a much higher low speed compression rate than twin tube dampers. 
The cautionary note is in drawing too broad a conclusion from your experience. For the E39 540, it definitely sounds like the Koni/Eibach is not a good pairing. However, the experience could very well be different for a lighter weight E39 (such as the 525), non-E39's, or E39's with stiffer springs.


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