**NOTE: on 3/20 I changed the title of this post because at first I just had a question (this post)...but now I am sharing my experience regarding replacing your 914 suspension with Koni Adjustable shocks because a lot of people asked or seemed interested. Jump to Post 13 for "The rest of the story"....

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It's been a while since I've posted a stupid question - heck I've been so busy lately and not done much with my 914's in months that its been a while since I've posted ANYTHING at all... (Papa Smurf is away at Dawe's Motorsports winter camp spending all our retirement savings and Huey has been sitting patiently in the garage waiting for nice weather...)

So here's my dilemma: I ordered a full set of Koni Sport adjustable shocks for Huey, and I got the coil-over set up from Ground Control for the rear. They came Friday, and I was excited to get working on them Sunday (was busy Saturday).

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So...after doing a bunch of things to our other cars that needed the lift, I got Huey up there, took off one of the rear Bilsteins (figured I'd start on the easy end first, easy remove and install right?) and looked at what I had in the new box, and what I had on the old shock. I realized I needed basically all the hardware that goes above the spring hat (washer, threaded collar (Porsche calls it a bushing) and rubber bushing) that was below the hole, and the bushing and washer above. Basically everything above the hat except the top nut (which they give as a lock nut).

This is where the stupid question comes in: Are there different threaded collars (bushings) for Bilstein and Koni? Look at these pictures: First one is the threaded collar, screwed all the way down on the Bilstein as it's supposed to - and the rubber bushing goes over it. The second one is as far as the collar will go...which is not at all because the thread pitch on the Koni is different!! Do I need a special threaded collar for Konis? Did they not send me something I should have? Suspension is something I've honestly never messed with...

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I'm going to call Ground Control later today, but thought I would throw this out there to the World braintrust and see what responses I get since I'm SURE some of you have upgraded to Koni adjustables...

Thanks!

I'm doing the same coilover conversion on my car... Except my Koni's are the red ones...

I think I remember reading that they fit everything except on version of Koni? I called them and they asked me to measure the OD of the shock to insure that the "threaded adjuster" would fit properly....

I haven't ordered a kit for mine yet, been recovering from hip replacement surgery... Hopefully be able to work on the car later in the spring....

Good luck, I'm interested in hearing what they say....

Thanks,

Steve

At the end of the day, you could use washers/bushing and a nut.

I would call ground control and see if they have the right part, but I would also not sweat it if they do not. Just get a bushing of the proper depth and washer and nut.

Rich

I would like to see others chime in here.

I have the same shocks, and I just looked at how mine are installed, and I dont have that piece that you have the arrow pointing to.
I just have a regular old nut on the top with the stock metal washer and the rubber "donut".

It makes me wonder if mine are installed correctly

Hey Rich
I thought of that, but then I wondered how the rubber bushings would work properly. Something needs to hold the spring hat in place doesn't it? And the rubber bushing fits snugly over that threaded collar. Without it, the rubber bushing would be loose, no? And since the lower rubber bushing rubs right up to the bottom of the chassis through hole, where would another nut go?

Stu, the pieces I'm talking about are down below the through hole in the chassis. You can't see them until you take the shocks out.

Well ok...learned something: The Koni Adjustables ARE different than EVERY OTHER rear shock, so they were supposed to come with their own threaded collar and top nut...I got the nut, not the collar.
So Ground Control is overnighting a pair to me. All good!!

Cool, could you post a picture of the final assembly?

So here are the CORRECT collars:

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they screw on nicely: (you don't use the big washer that's used with the stock spring hats)

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Then with the bushings on. For those that don't know...you slide the first one over the collar (first picture), then put the top of the shock up through the hole in the chassis, then put the other bushing, washer and nut on.

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This is how it looks fully assembled, though the shock tower body would be between the two bushings.

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Wow, i had the same issue but opposite a year ago when I went from Red Koni's to Bilsteins, the threaded collar wouldnt fit. I couldnt get an answer back then so I simply drilled out the threads of the collar and slid it on using only the top nut to hold it together.

That's interesting...I have a set of Red Koni and Green Bilsteins, and the threaded collars (and top nuts) are interchangable with both...

On Monday after my initial post and before I talked to Ground Control, I ran up to Black Forest and talked to John Forbes. He had an old set of Koni reds sitting around and gave them to me with their threaded collars because we assumed that Koni stuff would work on Koni stuff...and that it was the Bilsteins that are odd....wrong! I got home and they didn't fit. But they worked fine on the Bilsteins. When I talked to Ground Control, he called Koni. When he got his answer, he then apologized for not sending the correct collars and overnighted them.

Thank you for sharing that, and GC just got a customer for treating you right...

rich

Nice, glad GC took care of it quickly. Thank you for posting, I bought a set of those from another member, now I know it's missing some of the hardware. I was scratching my head when mocking up...

Saved to my subs

So here is "The Rest of the story" regarding replacing the shocks (front and rear) on Huey with Koni Adjustable Sport shocks...

Huey had Bilstein front and rear sport struts/shocks with it turns out only 140 lb springs and 21mm torsion bars. As you can see above, my plan was to replace these with Koni sport adjustables, 225 lb srpings, and use the Ground Control set up with the coil-over spring perches. Easy enough....

Once I got the threaded collars I needed (read above), I figured the rear would be a piece of cake. Wrong. First...the threaded part at the top of the shock is too short, so...when you screw the threaded collar on, put the rubber bushing over it, push it up through the body, put the top rubber bushing and big washer on...there's barely enough thread showing to bite on the nut!! I FINALLY got it to bite so I could screw it down, but was not 100% convinced that I have full engagement to the nylock nut, so I took it off and put a wavy lock washer on...making it even MORE difficult to get the nut to bite. After a while of swearing and having my wife help push the shock up as hard a she could from the bottom, I got it to start to thread and was able to crank it down...wow...

Rear done right? Nope...had to adjust the height. So I tried...but as far down as the spring perch will go, I'm still 1" higher than the car was before!! A whole Inch!! I'm down to the last threads on the coil over sleeve...so I can't go any lower. The only solution is shorter springs. They sent 10", I guess I need 8"...and now probably helper springs too... <sigh>

OK then...onto the front. But guess what? You can't put Koni inserts into Bilstein struts!

There's an article on Pelican Parts from Wayne that explains this..maybe I should have read this first?? http://www.pelicanparts.com/techarticles/1...s/63-Shocks.htm

So...I took the ENTIRE front assembly off - destroying both tie rod ends and one of the pinch bolts at the bottom of the strut/ball joint connection. (Not to mention dumping about a pint of brake fluid all over the garage floor...but that's another story!!) I'm hoping I can find a Koni strut assembly from a few local guys I know...we'll see.

But I figured while I'm here, I'll also replace the ball joints. One was kinda crunchy feeling. and it give me a good chance to really clean up everything under here.

So...lessons learned so far:
- Make sure you have all the hardware (I honestly still don't know about the front..yet)
- If you're car is low, get shorter springs if they're stiff because they won't compress as much as the stock ones will.
- you CANNOT use Koni inserts into Bilstein struts - check that first!!

I will post more once I get the Koni struts to complete the story.

IF I've done something wrong here, someone please tell me!! Did I miss something?? I don't mind learning as I go...frustrating that I have to keep waiting for parts, but that's part of the learning process. Suspension is one thing on Huey that I had never messed with, so it's interesting...

There should be a clip under the lower spring mount you can move down.

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IIRC, on Andy's car we removed just a bit of the threaded collar so the nut would go on a little farther. Just enough for the nylock to engage. The line in the picture is arbitrary, measure how much thread you need showing and only remove that much. Also, you can use the weight of the car to make starting the nut easier. Bit of a PITA to put the wheel back on and lower everything, but it makes the job easier, so it's worth doing.

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Boge struts will work also, Koni struts take a special top retaining nut,

Do the threaded collars have a counter bore in one end, maybe they are up side down on the shock.

Also check to see if the hat is all the way down..there may be s slight step on the shaft , not allowing to down further..

Carry On...

So do the 10 inch springs in the kit make the car sit higher than stock springs?

I think on my six I had 8" long 275 lb springs with a 100 mm tender spring. That matched nicely with 23 mm torsion bars.

The threaded coil-over collar is down as far as it can go...no further down

Not upside down, the spring seat that you spin to adjust actually has direction on it (up and down) and it spins the right way, so the threads go the right way...

Yes, hat all the way down. There is a step, but that's where it sits on to stop.

so yes...Boge struts work perfect, Koni it turns out do not with the hardware they send...actually, I don't think they would work at all (or at least the Koni's we tried). Look at the picture of the inserts in Post #1: see the tapered section at the bottom? The narrow tapered on the Koni strut housing goes much higher, meaning the insert does not go down far enough...like by almost an inch! So...find a set of Boge front struts, they work perfectly...


Unfortunately I don't know what stock height is so I can't comment there. When you order the Ground Control Kit, you specify the spring (rate and length). I didn't know length, so he sent 10", which is what he says they normally use....so maybe that's closer to stock height? Huey is pretty low...

Gotta thank Cody and John Forbes at Black Forest Racing for helping me out with these. Luckily, they had the struts (both Koni and Boge) so we could try them out, get them assembled, and have them ready to put back into the car.

But did you see from the pic, there is a snap ring on the shock itself. You have to remove everything from the shock to get to it. Spring, threaded collar, etc. If your setup came all assembled, you wouldn't be able to see this clip.

I think the threaded collars can be flipped as well.

I went through this problem with the rear a couple of years ago. I decided that the large washer, that was in your second and third pic is necessary to support the rubber bushing and weight of the car. I then bought two thinner nuts to lock against each other instead of one tall nylock bolt for the top of the assembly. Do not use an air gun to tighten down. I can post a picture of my nuts later.

IIRC my Ground Control threaded collars only went on one way. I thought of cutting the ID of the collar further down, but decided to have a machinist cut two or three more grooves into the shock body to get the car lower. They were the same depth and spacing as the others. I was running 225# springs, but recently switched to 200#.

8" springs is the only way to get the ride height low enough.
The top perch can be drilled out to float on the shock shaft.
That might allow the threaded collar to screw on a bit farther, thus allowing the nut to go on fully.

I pulled apart a spare set of Koni 8241 1050SPORT shocks with Ground Control adjustable springs to see exactly what was going on here. I tried to include a lot of pictures here so you can compare what I'm seeing with yours.

There is a 'ridge' section on the shock shaft that the spring hat is supposed to seat on. I was able to tighten the top collar-nut with the hat catching an edge and not seating correctly. And I included a picture of how much thread is showing when that problem happens. Looks quite a lot like what you're seeing.

It also took a bit of effort to knock the hat off the 'ridge' when I first disassembled it. So if the machining on the hat/ridge isn't quite matched, your hat may not be seating all the way. Check that the top of the 'ridge' is flush with the hat (see picture).

The Koni 8641-1077 Sport insert for the front 914 strut will work on Boge struts but not Koni housings. If you have Koni housings you'll need the 911 insert 8641-1039 Sport and this gland nut:

http://www.paragon-products.com/Koni-Gland...25.01.011.1.htm


The 911 insert is shaped a bit differently and will drop right in the Koni housing. We do this stuff all the time.

Ok, so I was just about to purchase the Ground control setup for the rears with bilstein shocks. GC has told me to go with 10 inch springs. I want to make sure I am able to lower my GT to the ride heights I commonly see pictured on this website. Can someone please confirm that for the bilsteins the 10 inch springs are the way to go? Thank You, Brett

I bought my package from paragon via a group buy BR put together iirc. I also remember having to be specific about the strut assem on the car. Such as which stock, 911, what ever. I've have seen a few threads similar to this one and I could never understand why. Mine went on right out of the boxes with no hassles other than installing the threaded collars upside down. As Jeff noted, there was step/land on one end that rests on the adj clip. The clip is enclosed by the collar when done right.

My GC springs are 8" tall...

T

Couple things to consider: with Bilsteins, you have more adjustability than with Koni because there are more "rings"'on the shock to rest the collar, meaning you can go a little lower.
The spring rate also factors in..:stiffer springs will not compress as much, leaving it car riding higher.
We have Koni Adjustible with 8" 225 lb springs. I did noticed that the lowest I could get the collar to sit on the Koni is higher than the perches were set on the Bilsteins I took off, so you may be ok with the 10" springs if you can get the collar low enough...