1990 Supernatural CR1 Coilovers - rebuild or replace?

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anton28
Posts: 12
Joined: Thu Nov 25, 2021 7:52 pm

1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by anton28 »

Hey guys,

I'm not sure if it's the age of my coilovers (1990), or just older technology of the dampeners vs what I'm used to, but I'm thinking its time to replace/upgrade my FX3 Callaway-equipped OEM coilovers on my 1990 ZR1/CR! The ride is just not "tight." I don't feel anything when I toggle the suspension adjustment switch. The car does not feel as stable as it should at higher speeds.

I have great experience with JRI's, but it would be nice to have the OEM set rebuilt/re-valved.

The JRI's are state-of-the-art, new tech, great ride with even better performance. How will that compare to a "new" FX Coilover designed in 1990? Have there been many advances in the dampener world over the decades?
bowtiguy
Posts: 42
Joined: Sun Aug 05, 2018 12:12 pm

Re: 1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by bowtiguy »

Anton,

There are many possible explanations for why you are not feeling a change in the FX3 suspension.

1) The controller is bad
2) one or more of the actuators are bad
3) shocks are bad ( or tired)

If the shocks still hold oil ( mine did not the first time I jacked it up) they should still function. All the CR-1's that I know of have had the FX3 systems upgraded to 94-95 parts. The callaway coil overs make use of the stock bilsteins with a grove cut in the body to retain the the lower hat via c-clip . Here is a video Ed did showing the components of a coilover.

https://www.youtube.com/watch?v=TM_ofmKV6CU

Basically, you can treat the system as if its a stock ZR-1. There is a wealth of knowledge on the ZR-1 registry site in regards to the FX3 system including How to diagnose & replace the components.

http://zr1.net/forum/showthread.php?t=16778 post #4 ( suspension)

I wanted to retain the FX3 suspension so I rebuilt my coilover system with new upper poly mounts and NEW bilsteins. They can be hard to come by and tend to be produced in limted runs. I've had and currently have Ridetech HQ shocks on a couple of vehicles and have been impressed.

If you choose to go aftermarket, keep the original callaway parts in case you decide to sell the car in the future. The next owner will thank you.
anton28
Posts: 12
Joined: Thu Nov 25, 2021 7:52 pm

Re: 1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by anton28 »

Wow thank you so much for the helpful info! I have a couple of follow-up questions.

Regarding the 3 items below. I think the shocks are tired. I don't see any check system lights on to indicate it could be the controller or actuator. Unless there aren't warning lights that go on when either is not operating properly.
1) The controller is bad
2) one or more of the actuators are bad
3) shocks are bad ( or tired)


Shocks do hold oil. How do I confirm if my system was upgraded to 94-95 parts?
If the shocks still hold oil ( mine did not the first time I jacked it up) they should still function. All the CR-1's that I know of have had the FX3 systems upgraded to 94-95 parts.

Does this mean I can use another brand dampner and fit the FXR system over it for adjustment?
The callaway coil overs make use of the stock bilsteins with a grove cut in the body to retain the the lower hat via c-clip.

Did you adopt the Ridetech shock to the OEM FX3 system?
I wanted to retain the FX3 suspension so I rebuilt my coilover system with new upper poly mounts and NEW bilsteins. They can be hard to come by and tend to be produced in limted runs. I've had and currently have Ridetech HQ shocks on a couple of vehicles and have been impressed.
callaway4fun
Posts: 365
Joined: Wed Aug 27, 2008 8:12 pm

Re: 1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by callaway4fun »

Also check your shock bushing as they disintegrate with age and you will have to have Callaway make them . I just replaced mine in August.
callaway4fun
Posts: 365
Joined: Wed Aug 27, 2008 8:12 pm

Re: 1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by callaway4fun »

Also there is a specific alignment for thr Coilover system. If you had the alignment done make sure it was done to Callaway specs it is different than stock.
bowtiguy
Posts: 42
Joined: Sun Aug 05, 2018 12:12 pm

Re: 1990 Supernatural CR1 Coilovers - rebuild or replace?

Post by bowtiguy »

anton28 wrote: Sun Nov 13, 2022 2:34 pm Wow thank you so much for the helpful info! I have a couple of follow-up questions.

Regarding the 3 items below. I think the shocks are tired. I don't see any check system lights on to indicate it could be the controller or actuator. Unless there aren't warning lights that go on when either is not operating properly.

Just because it doesnt light up, doesnt mean its working. Some one could have put tape across the warning indicator or pulled a bulb. You mentioned it doesnt feel any different when you adjust your suspension. I would look into Dynomites "solutions" thread in the tech section of the ZR-1 Registry for testing that control unit.


Shocks do hold oil. How do I confirm if my system was upgraded to 94-95 parts?

I'm pretty sure ALL CR-1s were, but a call to Callaway will confirm that for you.


Does this mean I can use another brand dampner and fit the FXR system over it for adjustment?

Anything is possible but you will most likely loose the adjustability of the FX3 system if you use anything other than the bilsteins designed for it

Did you adopt the Ridetech shock to the OEM FX3 system?
No, I ran Ridetechs on my 68 C/10 resto mod I built and recently put them on my 99 FRC. I bought new bisteins for my CR-1
Also, As Callaway4fun said. You will need (4) new upper shock bushing sets as well, mine were cracked and almost powder. They are cheaper through summit racing or jegs. You Just have to measure your shocks shaft O.D.
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