Both front Koni struts failed in 20k/2 years

[DoctorDaveLGT]

So this thread has kinda come full circle for me. While the car is at the shop for the Brembo install I gave them a set of GroupN tophats to replace my Whiteline ComC's and they found the front right shock was completely done for and the shock will compress completely on it's own from gravity. That's after about ~30k miles & 5yrs of being installed. Now there was a period within that time where the car was on a lift for over a year and all the suspension was unloaded the entire time. Idk if that contributed to the premature failure but it makes me wonder nonetheless. They're going to check out the rest sometime this week and I'll report back then.

I found some old forum posts late last night (sorry I forgot to save them and link) where Myles briefly discussed the differences between the KW's and the RCE's valving which has to do with the different springs used. The KW's use progressive springs while the RCE's use linear ones and the valving was changed on the RCE's to compensate. One of the other benefits of a linear spring is that it allows for more travel when compared to a progressive spring of the same dimension. See the link for a more in depth read on progressive vs. linear springs.

https://www.hypercoils.com/progressive-springs-vs.-linear

I ended up deciding to pull the trigger on a set of RCE Tarmac's and they should be getting delivered before the end of the week. Once the other Koni's are looked at I'm going to go through the warranty process to replace any need and then list those and the swift springs up for sale.

 

[SoobyDoobyDoo]

Aw man that sucks Dave, sorry to hear that. Appreciate the info on the springs, though, that's good reading. Now I'm curious to know what the failure mode is for both yours and Pleide's struts. I don't think this would deter me from buying konis eventually (I still think they're the best alternative to Bilsteins and coilovers for a strut that's an upgrade from the OEM), really I haven't heard of many issues over the years. I'm just curious how install error would lead to premature shock failure...now my quality engineer side is piqued.   

[DoctorDaveLGT]

Eh, it is what it is. I wasn't excited for the impromptu cost but I am looking forward to getting away from the Swift springs and to raise the car a bit for a little extra protection of the S402 lip. The odd thing was that there were no signs of a fluid leak on the strut at all so I'm curious to see what Koni says when I send it off.

I still have no complaints about the Koni's though. If the Subie was still a daily I'd just replace any under the warranty and be on my way, maybe change the springs, but still think they're a great choice all things considered. Have Koni's on the TSX wagon with RSR springs and love that setup. Although I find it a little annoying that those shocks give you 2 perch mounting points for a little flexibility in desired ride height compared to the Subaru.

 

[boxkita]

@Pleides When I sold my wagon, the BC were in need of a rebuild. Idk if new owner did it. 30k miles was maximum recommended from BC at the time especially given how I used them. 

Coilovers are a racecar part as such you should not expect passenger car life out of them. 30k miles between rebuilds should be a maximum number not a starting point.

Why does passing a shock dyno matter? unless you have a built/tuned suspension you are running on a consistent route, er, racetrack, being a couple pounds off won't matter. If you ever put anything other than a race spec (endurance 200tw) tire on your car,  the shock dyno report is more of a wall decoration.

If you racecar coilovers, the rce set with Myles weighing in is worth the money. You are paying for an expert to look at your usage and configuration and given you a recommendation. Once its on the car, you'll need to find an expert with a corner balance rack to further setup the car to get the maximum benefit from your purchase. You'll probably have to do the corner balance a couple times (testing on a consistent road course pays dividends along with data logging).

If you are building the car for you, start looking for a tire that provides the driving experience you want. I was/still am a fan of the Michelin SuperSports and their descendants. Its a consistent tire and handles well even until end of life. If you change tire brand/model every time, you don't really get a chance to build depth of tire knowledge. On the wagon, I got 10-15k miles per set. The gr86 is holding to this as well. Granted I don't track the gr86 so mileage has been a little longer.

Whoever you buy a set of c/o from, get a couple rebuild kits. The lgt is approaching 20yo, parts are getting hard to find. Oem parts have been on the shelf for 20 years in some cases so they are already toast before install. Aftermarket parts are 30k parts at best, less if you are flogging the car. Racewagon had 11k miles on the odometer when I bought it, many parts were beyond end of life when I upgraded to full whiteline.

Any parts you buy today, will be of lower quality. It was never a popular platform in the US so sti level parts stocking didn't happen. If you really want to be sure of quality, buy in quantity. Test each part and return the ones out of spec. Spec Miata shops buy in quantity of 100. Test all of them and make matched sets. It's expensive, time consuming and they are searching for the last millimeter of performance. Perhaps yer standards are a little high?

If you have engineering knowledge, you can find shops willing to make anything you want.  Ir you can contact a place like tssfab.us and ask them to make something for you. Whiteline still makes their full catalog. Megan still makes alot of stuff. ymmv

[Pleides]

On 11/14/2023 at 10:48 AM, boxkita said:

@Pleides When I sold my wagon, the BC were in need of a rebuild. Idk if new owner did it. 30k miles was maximum recommended from BC at the time especially given how I used them. 

Coilovers are a racecar part as such you should not expect passenger car life out of them. 30k miles between rebuilds should be a maximum number not a starting point.

Why does passing a shock dyno matter? unless you have a built/tuned suspension you are running on a consistent route, er, racetrack, being a couple pounds off won't matter. If you ever put anything other than a race spec (endurance 200tw) tire on your car,  the shock dyno report is more of a wall decoration.

If you racecar coilovers, the rce set with Myles weighing in is worth the money. You are paying for an expert to look at your usage and configuration and given you a recommendation. Once its on the car, you'll need to find an expert with a corner balance rack to further setup the car to get the maximum benefit from your purchase. You'll probably have to do the corner balance a couple times (testing on a consistent road course pays dividends along with data logging).

If you are building the car for you, start looking for a tire that provides the driving experience you want. I was/still am a fan of the Michelin SuperSports and their descendants. Its a consistent tire and handles well even until end of life. If you change tire brand/model every time, you don't really get a chance to build depth of tire knowledge. On the wagon, I got 10-15k miles per set. The gr86 is holding to this as well. Granted I don't track the gr86 so mileage has been a little longer.

Whoever you buy a set of c/o from, get a couple rebuild kits. The lgt is approaching 20yo, parts are getting hard to find. Oem parts have been on the shelf for 20 years in some cases so they are already toast before install. Aftermarket parts are 30k parts at best, less if you are flogging the car. Racewagon had 11k miles on the odometer when I bought it, many parts were beyond end of life when I upgraded to full whiteline.

Any parts you buy today, will be of lower quality. It was never a popular platform in the US so sti level parts stocking didn't happen. If you really want to be sure of quality, buy in quantity. Test each part and return the ones out of spec. Spec Miata shops buy in quantity of 100. Test all of them and make matched sets. It's expensive, time consuming and they are searching for the last millimeter of performance. Perhaps yer standards are a little high?

If you have engineering knowledge, you can find shops willing to make anything you want.  Ir you can contact a place like tssfab.us and ask them to make something for you. Whiteline still makes their full catalog. Megan still makes alot of stuff. ymmv

I guess my concern with the shock dyno example is that a set of four struts should be within a few % of each other in performance, not one or two failing a shock dyno out of the box. I would like to know I'm buying something where the tolerances aren't that wide and the parts are quality. As you said, there aren't a ton of options out there for these cars unlike the other Subaru counterparts, so you're stuck with what you can get. I do have Michelin Pilot Sport 4S tires on the car right now and those do a great job.

On 11/14/2023 at 10:10 AM, DoctorDaveLGT said:

Eh, it is what it is. I wasn't excited for the impromptu cost but I am looking forward to getting away from the Swift springs and to raise the car a bit for a little extra protection of the S402 lip. The odd thing was that there were no signs of a fluid leak on the strut at all so I'm curious to see what Koni says when I send it off.

I still have no complaints about the Koni's though. If the Subie was still a daily I'd just replace any under the warranty and be on my way, maybe change the springs, but still think they're a great choice all things considered. Have Koni's on the TSX wagon with RSR springs and love that setup. Although I find it a little annoying that those shocks give you 2 perch mounting points for a little flexibility in desired ride height compared to the Subaru.

 

Sorry to hear your set was bad, too. I'm wondering if later Koni kits used lower-quality parts. When they work, they work amazingly. They were more comfortable than my blown KYB struts by a mile and I never had compliants from passengers. The body roll was a little bit much given the softer springrate of the H&R springs, but not abhorrent given the era of car we're talking about here. 

 

I'm still undecided on the strut options. Ultimately, I now live so close to work that I don't worry too much about the mechanical bits of the car getting me A to B, but I like to put nice stuff on the car so it lasts. I feel a little bummed about the Konis not lasting all that long. If anybody here has more insight to using H&R springs with Bilstein B8s, do let me know. They're the only other decent-quality non-coilover shock available for our cars that I know of if you plan on lowering the car.

[Tehnation]

I think the issue with the Koni's are the springs, I am convinced that the premature failures are due to lowering springs. Lets think about who has had a failure and what springs they were running. I wanted the big drop and used some springs that may or may not been in spec . I don't ever see people complaining about failure with stock springs or ride height. To me it seems things get fugazi when other than stock springs or ride height are involved. And its usually only the front struts that get f'ed cause now u have all these other extra variables when you deal with sleeves etc. 

[Tehnation]

Would getting a bigger wheel like an 18" fill the gap better without dropping the car or less drop?

[Pleides]

On 11/16/2023 at 1:29 PM, Tehnation said:

I think the issue with the Koni's are the springs, I am convinced that the premature failures are due to lowering springs. Lets think about who has had a failure and what springs they were running. I wanted the big drop and used some springs that may or may not been in spec . I don't ever see people complaining about failure with stock springs or ride height. To me it seems things get fugazi when other than stock springs or ride height are involved. And its usually only the front struts that get f'ed cause now u have all these other extra variables when you deal with sleeves etc. 

I think most people are using the King or H&R spring sets with this car, which is what they've valved for, as I understand. The rears are still going strong on my car, so I suspect that might not be the issue, but I may be wrong.

 

10 hours ago, Tehnation said:

Would getting a bigger wheel like an 18" fill the gap better without dropping the car or less drop?

On a stock car, IMO an 18" wheel with appropriately-sized tires makes the car look like a monster truck. Just dropping the car half an inch will help with that on 18s. I think my car with the H&R springs looks awesome with 18s on it. 

 

 

[Tehnation]

18's seem the way to go, that way you can minimize the drop. Like most have said in prior posts dropping the car to low is counterproductive. Bigger wheels can give you the looks and performance IMO. What size tire? I want to get some wide wheels, like 9" or 8.5". I was thinking 245/35/18 tire on 18x9 wheel, which should fit without modifications.  

[Pleides]

6 minutes ago, Tehnation said:

18's seem the way to go, that way you can minimize the drop. Like most have said in prior posts dropping the car to low is counterproductive. Bigger wheels can give you the looks and performance IMO. What size tire? I want to get some wide wheels, like 9" or 8.5". I was thinking 245/35/18 tire on 18x9 wheel, which should fit without modifications.  

My car is on 235/40R18s in the second picture (summers) and 225/45R18s in the first (winters). For 9" wide wheels I would run a 245 at minimum to avoid stretch. The wheel wells are not huge on this car and you will need around 2 degrees of negative camber to fit those wheels and tires with the kind of drop my car has. I rub at full turn trying to remove myself from tight parallel parking spots. 

[Tehnation]

How wide? 

[Pleides]

3 minutes ago, Tehnation said:

How wide? 

8 inch wide wheels.

[Tehnation]

https://www.bagriders.com/vehicle/subaru-legacy-bl-bp-awd

Wahh... air ride? 1st 15 seconds! I think I may hold off on coilovers, this looks a lot more interesting. 

 

[Pleides]

I so desperately don't want to deal with the maintenance of an air compressor in my suspension system without a warranty from an OEM like BMW or VW.

[SoobyDoobyDoo]

6 hours ago, Tehnation said:

https://www.bagriders.com/vehicle/subaru-legacy-bl-bp-awd

Wahh... air ride? 1st 15 seconds! I think I may hold off on coilovers, this looks a lot more interesting. 

 

PM bagridersJohn he had a huge rebuild thread for his car. Haven’t seen him on here for a while since I believe he sold it but worth a shot to reach out to him for more info.