Koni or Other Replacement Struts

[bimmerscott]

The subject car is my wife's 2005 ZHP sedan (sadly it is an automatic, but hey, I have my M3). The struts are leaking - no surprise for a car with over 125K miles. The shop that is maintaining the car gave a quote that included factory replacement struts at over $300 each just for the parts.

The car rides about as firmly as my wife would like, so I'm trying to avoid any replacement that is going to be more stiff than stock.

The shop's service advisor told me not to use Bilsteins. He didn't say why and I didn't have time to ask. So I thought about Konis.

Koni STR.T Street Struts are available from Tire Rack and others for about $115 each. They're described as twin-tube, non-adjustable low pressure gas struts.

Koni Sport Struts are also available from Tire Rack for about $197 each. They're described as twin-tube, adjustable low pressure gas struts.

Has anyone had experience putting either of these struts on their ZHP? If so, how does the ride compare to stock? On the adjustables, how does the least stiff setting compare to stock?

Sachs also makes a low pressure gas strut for sport suspension (the ZHP suspension is essentially the Sport Package suspension) for about $90 and a different low pressure gas strut for about $100 that is not listed as being for sport suspension. Are either of these even worth considering?

Thanks for any input on these.

[KevinC]

"Don't use Bilsteins"? Would love to know his reasoning.

Your shocks may have only recently started leaking, but have probably been, for the most part, "dead" since about 50k miles. That's about all the stockers are good for. Based on your ride quality comments, I'd strongly consider going with Koni FSD's. Many here have them and I'll leave it to them to comment.

[BMWCurves]

A handful of people have Koni FSDs and say they're filled with unicorn tears for hydraulic fluid. Maybe they are, maybe they aren't. I have no experience with them, but they all seem to like them.

I replaced my worn factory Sachs shocks/struts at ~50k miles with Koni Sports (Yellows) and have nothing bad to say about them. I have the Konis set at 3/4 turn from full soft and they are more comfortable than the worn Sachs units, and have better performance as well. I'm sure your wife would be perfectly comfortable at full soft or even up to 3/4 turn from soft.

You might also consider replacing some other bits while you're in there. I have a thread on what I did for an "OEM+" suspension refresh that I did on my car where I wanted to improve on stock performance without sacrificing ride comfort:

http://www.zhpmafia.com/forums/showthread.php?16182-Help-with-Suspension-Refresh-at-50k-miles-10-years

My assumption on the Bilsteins like HDs is that I've heard they're more stiff compared to stock Sachs shocks/struts and most Konis that are adjusted to full soft, so not really what you're looking for in your wife's car.

[ZHPizza]

Muh boyz is right. If you want comfort and handling, then you want FSD's. I've been driving my ZHP with FSD's recently and it is an absolute pleasure even on rough roads. You won't have the 'readinesss' of a tight suspension setup, but the ride is so worth it.

[John in VA]

Have you checked out the Suspension portion of the forum? There are many shock & strut threads there:
http://www.zhpmafia.com/forums/forumdisplay.php?99-Suspension

[Oli77]

For diversity, I went with Koni Street STR and KYB in front. Very good setup, sport suspension, tight but compliant, nice. Too many choices out there, you are not tracking it so let your wallet help you choose.

[C00KIE M0NSTER]

I went from OEM ZHP shocks to Koni STR.T and the ride was considerably worse. Worse handling and worse comfort. Also, the build quality was poo poo. If you want a cheaper option I would get OEM Sachs struts.

[bimmerscott]

We bought the car used with about 90K miles on it, so they may have been replaced once before our ownership. They've passed the "bounce test" just fine, so they may not be as good as new, but they've been functional shocks, even now with the leaks. Anyway, thanks for the FSD suggestion.

[bimmerscott]

Thanks for the Koni Sport recommendation. The shop will also be replacing the LCA bushings, the oil pan gasket (leaking) and motor mounts (failing), but the steering and other bits down there check out good.

[bimmerscott]

Thanks for the warning on the STR.Ts. Sounds like they'll ride exactly the way we don't want.

[Go Horns!]

I put koni yellows on my ZHP, and at full soft the ride was similar to stock. Might have been even more compliant than the stock ride.

I put Bilstein HDs on my 335is, ride is considerably stiffer. But that is what I wanted.

[slater]

Thanks for the Koni Sport recommendation. The shop will also be replacing the LCA bushings, the oil pan gasket (leaking) and motor mounts (failing), but the steering and other bits down there check out good.

are you confident that they're sure it's an oil pan gasket? because the OFHG leak does look a lot like an oil pan gasket.

as for shocks and struts... i'd go koni yellow or FSD. FSD is probably best - set and forget. plus, magical unicorn tears.

[Aeternalis]

I run Koni FSD shocks and stock ZHP springs. The ride is wonderful, and responsive when I want it to be. A fantastic "street" damper, in my personal opinion.

[san]

I have koni yellows with Zhp springs on mine. Have had them for about 40k miles and no complaints so far. The adjustability of the yellows a nice to have feature but I haven't messed with it on the rear since the entire shock has to removed. The fronts I have played with a little but that's just out of curiosity than anything. I haven't driven a car with fsd's but I think you will be fine with either if you are looking for stock-ish ride.


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[Vas]

Koni Yellow and H&R Sport springs here. No complaints.

[Jconlin16]

Koni Yellow and H&R Sport springs here. No complaints.

+1 Very happy with the same set up!


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[bimmerscott]

So I ended up ordering the FSDs. Originally I was only looking for struts, and the FSDs are only sold as a complete set of struts and shocks. But based on the Tire Rack comparison and other comments here, FSDs are exactly what we want, so that's the way we'll go. Thanks for all the advice and comments!

[ZHPizza]

So I ended up ordering the FSDs. Originally I was only looking for struts, and the FSDs are only sold as a complete set of struts and shocks. But based on the Tire Rack comparison and other comments here, FSDs are exactly what we want, so that's the way we'll go. Thanks for all the advice and comments!

You won't be disappointed. MY ZHP with FSD's rides significantly smoother than my touring with OE non-sport suspension. Also smoother than my 2015 Mazda 6 with OE springs, FSD's, and cushy sidewalled tires. It's like they were made for the e46 specifically.

[ELCID86]

I went Koni yellow fwiw. Like em.


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"ZHP is a garbage option anyway- just some cosmetic upgrades with a different cam and diff to claw back some of the performance lost fitting those hideous and heavy wheels. Any 330 with a 3.46 diff will smoke a ZHP every time. The whole Mafia thing reeks of childish behavior." - anonymous E46 fanatic