DIY coilovers

[Dr.Jeff]

Here is what I did

Thanks Paul. That answers my question; the Bilstein inserts you used are indeed for the early Mk1 VW (i.e. the narrower body/rod rather than the inverted version) and they are the special "short" version for lowering those VW's. That makes more sense, as I know the standard units are too long. Those Bilstein inserts are a bit pricey but I've always liked their products. As for getting them revalved, Bilstein changed their policy on that a couple (few?) years ago. They no longer offer such services, only repair of worn or faulty units. For custom work they refer to a couple of authorized independent service facilities, which I've found to be extremely difficult to work with and very overpriced. But it can be done.

By the way, in your linked thread, are some of the pictures currently shown in your detail work not correct for the dialog? It appears some images are lost, so I might just be reading the wrong words for the image shown. Thanks

 

[rozap]

Dr Jeff,

Thanks for those pictures, very helpful. And yea, that was basically what I was thinking, but used the wrong words . Are those Koni 2170's and 2169's? That is what my car has (it's an 85). I was thinking a 300lb/inch spring rate on the rear and 200 for the front.

Rx1900,
I actually had just assumed the car had the stock setup, but it has the Koni struts, which I think changes things. The car was $500 so I had assumed stock stuff. The goal is a 24 hour of lemons race, so it'll be mostly track use, and the goal of the coilovers is just for a bit more clearance for wider wheels (15x7's), ride height adjustment, and extra stiffness.

 

[lookforjoe]

I used Bilstein B8's (34-184530) on all corners. VW application, perfect length. Pretty sure it was Doug who suggested them to me. I've been very happy with them. Less happy with the heavier rate rear springs I needed to switch to, but with the new drivetrain it should be OK.

 

[rx1900]

Dr Jeff,

Thanks for those pictures, very helpful. And yea, that was basically what I was thinking, but used the wrong words . Are those Koni 2170's and 2169's? That is what my car has (it's an 85). I was thinking a 300lb/inch spring rate on the rear and 200 for the front.

Rx1900,
I actually had just assumed the car had the stock setup, but it has the Koni struts, which I think changes things. The car was $500 so I had assumed stock stuff. The goal is a 24 hour of lemons race, so it'll be mostly track use, and the goal of the coilovers is just for a bit more clearance for wider wheels (15x7's), ride height adjustment, and extra stiffness.

Aha !!! well that is cool if it came with Koni struts.

But do watch out - there was a member here who had a habit of painting old stock struts in Koni colours and putting Koni stickers on them !!!

but yes...if you do indeed have a full set of real Koni struts, they would be a great basis to turn them into coilovers for budget racing.

However....before you get too carried away with planning for that...you will have to check them out pretty carefully. They are likely at least 20 years old by now, and probably well past their prime. And will need a rebuild.

Remove them from the car - do you know how to do that ? - and then remove the spring and upper mounts - there are a bunch of pieces in there. Do you know how to do that ?

Then fully extend the bare shaft of the shock. Is there firm and even resistance when you do that ? Now comes the most crucial part. When fully extended - VERY carefully examine the chrome shaft for any pits, rust, gouges, wear, etc. Any damage there - they are trash. Bin them and move onto another plan....

If...the chrome shafts past muster...then the shocks can - and likely should - be rebuilt. Using them as is would likely be a bad idea for competition use.

You could send them to a Koni service centre where they could be serviced - if they still have the parts to do so. This will likely cost you about $250 per shock.

Or.....you could try to rebuild them yourself. There is a great tutorial on this forum for doing that. Basically - you take them apart, clean all the innards, install new seals, and fresh fluid.

Then turn them into coilovers and go a-racing.......

 

[Dr.Jeff]

I used Bilstein B8's (34-184530) on all corners.

That is the same insert that PaulD used; in his link they were described as "P30-0032-M1", but that crosses over to the number you posted (34-184530). They are the "short" VW Mk1 inserts. Still available but not cheap - however no different than any Bilsteins. A good choice for converting stock X struts assuming you have the ones with a removable insert.

 

[Dr.Jeff]

Are those Koni 2170's and 2169's? That is what my car has (it's an 85).

I'd have to go back and double check the part numbers. But for the most part there were only two choices from Koni for the X; fronts were the same number for all, rears had a early and a late year model version (i.e. 4-speed and 5-speed X's). However it has been shown that either can fit any year X if the matching top spring perch is used. Otherwise they are the same internally. The ones I posted pictures of for the coil-over conversion are the same Koni's. So if yours look like them then they should be real Koni's (note I already removed the lower spring perches in those pics). In particular look at the large "nut" or "cap" at the top of the main tube (holds the insets into the housing). The Koni one is different from any of the Fiat ones. Koni uses two small holes in that nut to remove/install it, Fiat is different. You can see it better in one of the pics in my Koni rebuild thread:
https://xwebforums.com/forum/index.php?threads/suspension-koni-strut-servicing.36142/

I agree they should be serviced even if they feel good. The fluid is a petroleum product and breaks down with age as well as use. And the fluid Koni used actually wasn't that great; there are much better suspension fluids available now. Plus you will surprised how much debris you will find inside. This also allows you to use a little heavier weight fluid if you want to make them a tad stiffer without revalving them (poor man's approach). Koni changed the weight of the fluid over the years, kept getting lighter for more comfort. So replacing with heavier would be better for track use.
As "rx1900" described, inspect them. But if there are no signs of fluid leaks at the top of the main tube (strut body) then you should be fine (unless all of the fluid has leaked out). And if there is a little leakage (very likely) they may still be good provided the shaft isn't damaged. All of the parts needed to rebuild them are available without going through Koni, except for the main top seal. That is a unique design and is very difficult to change. Unfortunately Koni no longer sells parts directly, so you will be referred to one of a couple independant service sources. And they tend to only do full rebuilds themselves, and won't sell parts. So if the top seal is decent then leave it alone.

 

[ashmowerman]

That is the same insert that PaulD used; in his link they were described as "P30-0032-M1", but that crosses over to the number you posted (34-184530). They are the "short" VW Mk1 inserts. Still available but not cheap - however no different than any Bilsteins. A good choice for converting stock X struts assuming you have the ones with a removable insert.

Ive actually used these strut inserts as you and it an easy install with sealed X struts. the Bilstein inserts come with two strut nuts one has an internal thread and one an external. cut the top off your X strut and weld the external nut on top grind out the centre and insert the new strut and tighten down with the internal one.

 

[ng_randolph]

Aha !!! well that is cool if it came with Koni struts.

But do watch out - there was a member here who had a habit of painting old stock struts in Koni colours and putting Koni stickers on them !!!

Not to forget the famous "Roni" struts:

 

[Dr.Jeff]

There is a foreign company that makes "replica" Koni's for motorcycles by the name of "Ikon" - (letter jumble).

 

[Dr.Jeff]

Ive actually used these strut inserts and it an easy install with sealed X struts.

'Ash', that's brilliant. I never thought of using both inner and outer style nuts together. Old Mk1 VW struts came in two versions (actually more, but two in this respect); one with the top of the tube threaded internally and one externally, hence why Bilstein provided both nuts. Did you start with the X1/9 struts that were threaded from the factory, or when you said "sealed" did you mean the units with non-removable inserts (i.e. no threaded top nut)? I ask because I'm wondering if your method could work on the sealed non-threaded struts....since you are cutting the tops off and welding on a new threaded end. I'm not sure what the insides of the sealed struts look like, they might be different and the Bilstein insert may not fit. But if they do then there are LOTS of worn out KYB struts that might work for this. However I recall the KYB's were a different diameter strut body, so maybe they won't work. And be aware that some are highly pressurized before cutting into them.

And how did you deal with the top mount, where the center strut rod mates to the Fiat mounts? I see the pic but need some details. Thanks.

 

[lookforjoe]

I assumed he meant standard issue struts, since he says 'easy install with sealed X struts" . Brillant idea, I hadn't even thought of that as an option. I wonder if the bicknell sleeves would fit on the Fiat tube. I have several stock tubes. Need to research this as alternate options.