Topic: Koni Z0K Suspension Testing and Install Process

[kennysabarese]

Uranium beat me to it, but I am going to be going with the KZ0K setup of Konis Sport SA shocks and GM GXP Z0K springs. I already have the Z0K Swaybars, DDM Backbone, and ProBeam. I am planning to do this install myself, and so I will document the process here when I get to it. But first for educational reasons, I did some testing of the components before I will install them.

I was very lucky to get a set of Koni's used from member Salstice for a great price!  

Salstice sent the shocks to me with a bunch of the stock parts prepared (holes drilled) which will make the installation much easier for me. They were also in great shape, just a little scratched up.


I ordered my Z0K springs and saw that the tags for the rear springs did not match what Flash's Owner has in his post about suspension specs. There were no part numbers on the tags that matched with what I was expecting. I contacted the dealer who contacted GM and was unable to get any verification. So I wasn't sure if I had received the correct springs.


In doing some reading and research I learned that shocks and springs can sometimes not match each other from the factory. I decided to have them shock dyno'd to see how good they are. I also wanted to get the springs tested to see if they matched the published spring rates.

[kennysabarese]

So I took a trip over to Stimola Racing/SRP Engineering http://www.srpengineering.com/ in Long Island to get my shocks and springs tested. It was a long distance, and I probably could have gotten this done anywhere, but Joe Stimola and his son James are very well known shock tuners. They mostly work on shocks for professional racing teams. They do all the shock setup for Phoenix Racing, who, as you most know, built the SCCA winning Solstices of Don Knowles. 

I worked with James, and he was very knowledgeable and friendly. It was amazing just to see an entire shop devoted just to shocks and springs. These guys had a boneyard of broken shocks from all kinds of crazy cars. Every type of shock you could imagine and more. A great part of visiting was just learning. He gave me a tour of the shop and showed me the insides of shocks, how different brands differ from each other in setup, and how things break and wear out inside the shocks after being driven hard. An incredible learning experience.

The shock dyno is a very neat device. I'm sure some Googling can explain how they work. Here is a photo of a shock dyno and a video of my shock being tested. It's an amazing video lol



[youtube]http://www.youtube.com/watch?v=9JXjgHO-_2k[/youtube]

The spring tester is much simpler, just a piston style jack on the bottom and you jack it up with the spring inside and it reads how much pressure is pushed onto the top part.



The back springs are meant to be 285, front 211. My results were as follow
Front 204 and 215
Rear 280 and 282

So the springs were the correct ones! 

The font were pretty far from each other, so I'm getting two more springs sent over so I can try to find a closer match. The rears are fine. If I can't get a good match on the front, I will use the harder spring on the drivers side.

As for the shock dyno results, 3 of the shocks were very close, one of the front shocks was very off. Here is the graph of the results for the fronts:
[attachment=1]

I could use the shock adjusters to get the two fronts to match each other, but then it will make keeping track of adjustments more difficult as they will each have a different starting point. So I am looking into the warranty details and if I can get one replaced great, if not I may just order a new one. Hopefully I'll get this resolved this week. More to come.

[Uranium-238]

One of my rear springs had one of those green labels as well. The other did have a regular GM label with the correct part number.

I still need to get the probeam and backbone, be interesting to see how those affect the car.

[wspohn]

If the one shock is still properly operational, I doubt that you'll get any warranty claim honoured.  AFAIK, they never represent that the shocks will all be within any particular tolerance.  I'd just adjust the one that is off up a click or two and record the different starting point.

[snaponbob]

That shock can be rebuilt !!!!  Not real expensive. Let Stimola do it !!!!!

[kennysabarese]

That shock can be rebuilt !!!!  Not real expensive. Let Stimola do it !!!!!

James told me that rebuilding may be more expensive then replacing it. He's going to get price for a single replacement from Koni.

I doubt they are going to help with the warranty, but can't hurt to try.

[LatinVenom]

I am going to be installing the Z0K shock\springs(already assembled).
Every one quotes 2 hour for the front and 2 hours for the back.
Do you really have to unbolt the steering knuckles(front suspension) to do the installation and also take the calipers off?.

[Uranium-238]

Uh, we disconnected the a-arms from one side of the knuckle, but we didn't mess with the calipers at all.

[DeepBlueGXP]

Calipers never come off. 

[LatinVenom]

When you say one side of the A arm, are you saying the bottom one where the shock is bolted to it?.
Also GM cautions about not rotating the knuckle while taking the nut off. GM say to use manual tools to do this.
Can someone shed some info on this please.
Thanks

[NormSky]

Probably want the control arm bolt held while using a wrench on the nut. The bolt on the control arms are usually pressed in aluminum.

Norm

[snaponbob]

It is starting to sound like people are mixing up terms. LV, you seem to be talking about the half shaft nut on the rear. Yes? No?

Anyway, to swap the fronts, disconnect one sway bar end on each side, separate the tie rod ends, and pop the ball joint loose (upper or lower is your choice, but I do the lower), and the unit will come out in front of the lower control arm. On the rear, do the same with the sway bar and toe links. You do NOT need to separate any of the rear ball joints. The unit will come out in BACK of the lower control arm. On my car, I have filed off about 1/8" - 3/16" of the upper shock studs at the rear to make it easier to handle the nuts and wrench.

[snaponbob]

Probably want the control arm bolt held while using a wrench on the nut. The bolt on the control arms are usually pressed in aluminum.

Norm

The upper control arm nuts are welded (IIRC) while the lowers are not. Book calls for a lot of torque, 122 ft/lbs, on the lower bolts and 81 ft/lbs on the uppers bolts. Lower ball joints are 30 ft/lbs PLUS 135 degrees and uppers are 22 ft/lbs plus 150 degrees.

[LatinVenom]

No I was talking about the front A arms and the bolt joints. GM does not say anything in their repair manual about the the sway bars.
They talk about taking the wheels off then the calipers, and lower bolt joint. This is where they caution about the damage and using hand tools.
On the rear is just the tires and the control arm that has the adjustment for the toe. They say not to change the nut adjustment, and just take the arm off, then the shocks will come out once you unbolt them.
This whole thing start it because when I asked the dealer how long it would take, they quoted 1 hour per shock and I thought this was a bit to long, thus the questions to those members that actually have done the procedure.

Thanks to all that responded.

[kennysabarese]

Going to get my shocks tomorrow! Car will be up on jackstands for a few days

[IBDRINKEN]

Kenny,

Will you be needing the 15mm

[Critterman]

Do you have an extra?

[kennysabarese]

Allright well, this thread died for quite a while cuz I never got around to installing the shocks and springs.

I finally started working on the project. Last mod meet I picked up a set of 4 NA shocks and springs, 2 of them were complete. So I took the bump stop and cover off of them and made to complete Koni Z0K setups.

If anyone has some spare shock bump stops and blue covers laying around let me know

So I compressed the springs:
[attachment=1]

Then you need an hex wrench to keep the rod from spinning when you loosen the nut:
[attachment=2]

Remove the bump stop and cover, move them over and done.

One thing I noticed is that the shock tops that came with the Koni's (from a kappa owner) had black and the others blue. Anyone know the difference?
[attachment=3]

[snaponbob]

Sure ............................ the colors !!!!!!!!!!!!!!!!!!!!!!!   

  It was to easy.

[Ag_Sky]

Just in time for the autocross season! 

I completed the installation of the Koni SA's, ZOK LNF springs, FE3 front sway and ZOK LNF rear sway bar last night. It went pretty smoothly except for the insulators and brackets on the sway bars. I didn't have the right ones. I was able to mount them by using FE2 front pieces, the FE3 rear pieces and some 3/8" flat washers between the brackets and the frame. This provided enough space for the insulators to hold the bars without gripping to tightly. This will be a temp solution until I get the correct brackets and insulators.

Here's a trick I used to separate the ball joints. This works because the nuts have a flange at the base of the nut. After backing off the nut on the ball joint to near the top of the bolt I place a socket on the nut and hit it a few times with a 1 lb sledge hammer. The ball joint popped loose after a couple of whacks. EasyPeasy!

Look out STR! 

[snaponbob]

Just in time for the autocross season! 

I completed the installation of the Koni SA's, ZOK LNF springs, FE3 front sway and ZOK LNF rear sway bar last night. It went pretty smoothly except for the insulators and brackets on the sway bars. I didn't have the right ones. I was able to mount them by using FE2 front pieces, the FE3 rear pieces and some 3/8" flat washers between the brackets and the frame. This provided enough space for the insulators to hold the bars without gripping to tightly. This will be a temp solution until I get the correct brackets and insulators.

Here's a trick I used to separate the ball joints. This works because the nuts have a flange at the base of the nut. After backing off the nut on the ball joint to near the top of the bolt I place a socket on the nut and hit it a few times with a 1 lb sledge hammer. The ball joint popped loose after a couple of whacks. EasyPeasy!

Look out STR! 

Ya know ?!?!? That idea of using the socket is SO simple ................ I LOVE it.

[Gentleman Jack]

Ya know ?!?!? That idea of using the socket is SO simple ................ I LOVE it.

Some of the simplest ideas in the world are the best... get a crappy socket that you can beat on if needed so as not to damage one of the good ones...

Unless you are SOB and you have more tools than the rest of us combined and can get new ones at the drop of a hat 

GJ

[kennysabarese]

So I finally got the shocks and springs installed. Took me about 9 hours across a few days. I had to do one over cuz I had forgotten to torque the shock nut on top.

Just got back from an alignment. Went with the Z0K specs plus a more camber in the front. Car feels great so far.

I am one turn from full soft on all four corners. I'm gunna play around with them soon to see how much I notice when it's changed.

The last thing, I want to build a custom tool to adjust the shocks. I drilled holes but I still can't get the Koni plastic thing in there. I'd have to drill a massive hole and I'd rather not. So I just need something longer. It's just a piece of plastic with a slot cut out of it. Should be pretty easy to figure something out.

[attachment=1]

[kennysabarese]

Pics of it after being lowered. stance is much better.

[attachment=1]
[attachment=2]

Oh and I think one of my stock shocks was bad Didn't a few other folks have problems with these?

[attachment=3]

[Critterman]

I'm thinking you nailed that one about a bad shock
a little advise, take it for what it is worth.  Cut an 1"-1.5" off the front mud flaps, otherwise they will hit speedbumps and rub around hard corners (don't ask).  And generally eat up your lower fenders.