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Koni Yellow PN's Bilstein #'s

Posted: Fri Aug 19, 2011 9:18 am
by 3X00-Modified
Use this information at your own risk... I take no responsibility for any failures when doing this modification to your vehicle. You are fitting a part to the car that was not intended for it so the chance of some issue is always present.

If you can find them J-body Inserts that you can use in a regular front strut housing for a Beretta with bushing I designed or something else to space it properly.
P/N# 8641-1454 Sport

A second Option that is known to work thanks to the J-body guys
-2nd gen Mitsubishi Eclipse (90-94) inserts can also be used. They are 15mm shorter and have more travel than the 3rd gen inserts. The only real reason for using these would be for more overall suspension travel.

Saab 900 94-98 Rear Shocks that can be adapted to 94 and older rear suspension. All you need to do is drill out the upper mount to accept a 14mm bolt vs the 12mm that is on the stock shocks.
P/N# 8041-1191 Sport

Optional Bilstein Shock
Bilstein PN F4-BE5-2538-H0
Saab 900 94-98
Once again another shock that fits the 95+ but was discontinued so if you can find this PN somewhere see if they still have any.
KONI 8041-1202SPORT Ford Thunderbird
I have a open e-mail with them asking if there is any other option that is close to that setup. I may try to pick up some that are on Amazon listed as in stock somewhere.

To use the Thunderbird shocks above you will need to purchase some cheap aftermarket shocks they come with a lower bracket to mount them. Just narrow the collar on the shock by a tiny amount to fit this width and your good to go. Only difference between the Saab's and these Thunderbird ones is the valving is a bit more aggressive and the lower mount is a 14mm bolt vs a 10mm bolt.
Lower bushing is also 41mm wide vs 36mm. Hence the need to narrow it to fit the bracket.


Procedure for front strut build is below, I have more photos towards the end of the thread with my custom bushings I made.

Length numbers for each shock.
87-94 Beretta Rear Shocks, 21.73" Extended, 13.58" Compressed.
95-96 Beretta Rear Shocks 18.62" Extended, 12.13" Compressed.
KYB 94-98 Saab Rear Shocks 21.42" Extended, 13.39" Compressed.
Bilstein 94-98 Saab Rear Shocks 21 15/16" Extended, 14" Compressed.
Koni 94-98 Saab Rear Shocks 21 15/16" Extended, 13.25" Compressed.
Koni 1989-97 Thunderbird/Cougar Rear Shocks 19.21" Extended 11.85 Compressed

Info regarding using Saab 900 shock on 95-96, for a 95-96 fitment you will have a shock that is 3.3" longer at full extension, and 1.87-1.12" longer at full compression depending on which shock you use... I'm still unsure of what length you NEED to ensure you do not bottom out the shock before the factory bump stops. My first attempt with Saab Konis is about 1" less of travel. I HAD 3 1/8" of travel with the KYB's and I now have 2" of travel with the Koni's.(Shock will bottom out with the suspension, I advise you to get the Thunderbird shocks and build a lower mount for them to avoid this since you can damage the shocks.)

More Koni shock info comparing many dampeners.


I responded to the prior email a few minutes ago. We cannot do a group buy that is organized by us but we can build a production run for a single company or individual to arrange and pay for and that person can organize a group buy or sell them however they want.

I cannot send drawing of the inserts themselves but the key specification of the insert Outside Diameter is not stated on the drawings anyway. Every application is vehicle specific and by definition an insert must be an exact dimensional fit inside the strut house for it to be secure and safe. We do not have any data that shows the IDs of the OE strut housings. I have done a review of the maximum extended and minimum compressed lengths and the valving specifications at two piston speeds (0.33meters/sec. or 13.0 inches/sec and .13 meters/sec or 5.1 inches/sec.) and find the specs for the Cavalier (8641-1494Sport ), Eclipse (8641-1231Sport) and the old Beretta/Grand Am (8641-1239Sport) to be quite different.

Max. extended (mm) Min. Compressed (mm) Rebound damping max/min (Newtons/sec) Compression damping (Newtons/sec)

8641-1239Sport 580 417 1300/650 @ .33 m/s 400 @ .33 m/s
500/250 @ .13 m/s 280 @ .13 m/s

8641-1454Sport 567 400 2500/1250 @ .33 m/s 700 @ .33 m/s
1500/750 @ .13 m/s 400 @ .13 m/s

8641-1231Sport 528 375 2100/1050 @ .33 m/s 900 @ .33 m/s
1320/660 @ .13 m/s 650 @ .13 m/s

Looking at the data, dimensionally the Beretta and Cavalier units are similar with Cavalier being ½ to ¾ inch shorter but the Cavalier is nearly double the rebound and compression damping forces of the Beretta. Although the valving of the Eclipse unit in rebound is in between the other two cars, the compression damping is much higher and most concerning the max and min dimensions are much shorter. Because of the way that it is designed, takes loading in the suspension, and makes beam strength or resists bending, It is extremely important that you not run too short an insert in a car or have it too far extended as the strength drops very rapidly as you extend it more than it was meant to be based on the vehicle ride height. Over-extending an insert is the primary way for failure when cross referencing part numbers so simply putting a very short strut insert in a car is often a very bad idea in reality.

Looking at the rears, here are the specs:

Max. extended (mm) Min. Compressed (mm) Rebound damping max/min (Newtons/sec) Compression damping (Newtons/sec)
8040-1133Sport 573 367 1700/850 @ .33 m/s 330 @ .33 m/s
560/280 @ .13 m/s 200 @ .13 m/s

8041-1309Sport 614 434 2000/1000 @ .33 m/s 300 @ .33 m/s
560/280 @ .13 m/s 200 @ .13 m/s

8041-1191Sport 560 337 1500/750 @ .33 m/s 450 @ .33 m/s
890/445 @ .13 m/s 200 @ .13 m/s

The Cavalier rear shock is the outlier here with a much longer length (about 4 inches compressed) than the other two. It makes the most rebound force but the least high piston speed compression force.

Hopefully this data provides some insight but I think the key takeaway is that the Eclipse front insert is likely to be a bad idea unless you do a great deal of research and confirmation and the car’s ride height is sitting considerably lower than on the others.

Best regards,
Lee Grimes
KONI America
Automotive Product Mgr.
1961 International Way
Hebron, KY 41048
Cell (859) 630-9350
Desk (859) 586-4100 ext. 316
Fax (859) 334-3340

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 9:21 am
by 3X00-Modified
Only attempt if you have the knowledge and tools to do so. This can very well be a difficult job for a novice.

WELL I finally got some free time to install the Koni's that have been sitting around a couple months. I used a set of OEM Delco struts from a 1996 Base (Daves base)

Here are the pics

stock strut

measure 40mm

cut the old cartridge out


remove cartridge from housing and drain oil


grind sharp edges

drill big hole on the bottom to accept the bolt



You will need to make a bushing to fill in the gap, exhaust tubing works well

Install Koni yellow adjustable strut cartridge


The strut housing will be sandblasted and powdercoated. Thats why I didnt post finished pics. Otherwise I would grind the rust and repaint.

Reinstall spring, then alignment and enjoy.

Pics to follow someday hopefully.

Found some pics on the J-body site... filled in what I could and I will be updating it with my progress of my install when my inserts arrive.

EDIT 6-8-16
Pauly recently did this with the Mitsubishi inserts and the total cut off for the strut housing is 64mm vs the Koni measurement of 40mm. These inserts are shorter than the J-body's. This ended up with a insert stickout like this.
You want to have at least this much of the insert visible.


In conjunction with the longer cut to use the mitsubishi inserts you also need to compensate for the different top thread vs the older J-body versions. There is a step that messes with how the top hat fits everything and you need one thin bushing to take up that extra space. Bushing is 0.855 OD x 0.590 ID x .500 thick. The other sleeves that I was selling to weld into the strut housing also needs to be tighter since the Mitsubishi strut housing was a smaller diameter.(dimension coming) The J-body ones are larger and if you use the older sleeves then the insert will move around some which is not good.

Spacers you need for the top hat's

Where the spacer goes.



With Top hat installed.


Completed strut

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 9:23 am
by 3X00-Modified
Steph (and all) -

Where can I get koni (yellow) shocks for the rear of my GTZ? I realize that I can use the Gen 3 cav struts for the front - as many have done. I have tried three of the major locations that google has provided for me that could carry the original Koni's for the berettas - and I've gone as far as completing the orders, only to be told they no longer have them.

I read somewhere on that I could utilize Koni's for a Saab. Here is a clip of what was said:

"There is a set of yellows that will fit the rear, but it does require some work and it won't be valved correctly unless you use a stiffer rate spring. 94-98 Saab 900 shocks are the same length, stroke, and have the same mounting style. The biggest difference is that the stud is 12mm instead of 10mm, so you need to ream out the shock mount."

Is true? I'm just looking to have a fully adjustable suspension - Does anyone know any reliable source for the Koni's in the rear? Thanks in advance.

'92 GTZ
'88 GTU

Other info from an old post about the J-body guys doing it. ... 67951.html

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 9:45 am
by 3X00-Modified
I think I will be the first to do the Koni's on the rear of a 95+ car... As long as I can verify the PN from Alex.... Shitty part is the Saab 900 PN is $40 more expensive than the previously though Saab 9000 number... damnit! lol

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 10:35 am
by heavywoody
I've been planning on this for my 95 for a few months now, just haven't had time or finances to make the plunge (yet). Should have things together very soon.

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 11:22 am
by 3X00-Modified
I'll start with the rears first... the fronts I'll do over the winter.

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 12:39 pm
by Barry
Woot woot!

Finally some real struts and shocks going into L bodies. Eff kyb crap

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 1:08 pm
by KFLO 93 GT
I'll be watching with interest. My car needs some ground control coilover inserts upfront with some stiff ass custom springs in them.

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 3:48 pm
by spacecadetz26
dont have any clue as to where those pics are :(


My write up still exists? I havent seen it in a long time or do i remember what site it was on. lol

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 4:31 pm
by 3X00-Modified
Yeah it was on this site, if you search for Koni Shocks it comes up.

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 4:33 pm
by spacecadetz26
shocker it was never pinned :P

i had the pics hosted on his ftp site dont know if he still has them.

Re: Koni Yellow PN's.

Posted: Fri Aug 19, 2011 10:59 pm
by 3X00-Modified
everything got transfered over to Will.... I could ask him if he ended up with those photos.

Re: Koni Yellow PN's.

Posted: Sun Aug 21, 2011 1:17 am
by Alxsmt
I might have a bunch of pics from mine somewhere. Its nice to finally see someone post this!

Re: Koni Yellow PN's.

Posted: Sun Aug 21, 2011 8:46 pm
by Alxsmt
mine are from a 94 saab 900. part number matches what you posted 95-98. I paid 181.00 each on tirerack.. only 161.00 now!

Re: Koni Yellow PN's.

Posted: Mon Aug 22, 2011 9:45 am
by 3X00-Modified
first post updated with links to cheapest price. Race Mart for 136 on rears and 148 on fronts.