: Question about using Eibach springs from GC kit - without the GC perches



repenttokyo
05-23-10, 11:32 AM
I am considering picking up a pair of Eibach springs that came from a GC kit. I would be installing them without the GC perches - just using the springs. What would the drop be like? Is this a bad idea? i believe they are 500 lb springs.

I asked this in the mods section, but haven't had any luck so I thought I would broaden my pool of experts out - if this is inappropriate, please let me know!

tweeter81
05-23-10, 12:03 PM
Going from memory here, I believe the drop for a CTS-V is stated by Eibach to be 1.6" in front and 1.2" in the rear. But, you need a spacer to install on top of the rear nivomat load-leveling shocks to fool them into not pumping the rear of the car up. I am not sure where you can get the spacer from, but I do know that if you just buy the GC Kit, it comes with everything you need. I would highly recommend that option, that way you have all the adjustability you need.

repenttokyo
05-23-10, 12:05 PM
Going from memory here, I believe the drop for a CTS-V is stated by Eibach to be 1.6" in front and 1.2" in the rear. But, you need a spacer to install on top of the rear nivomat load-leveling shocks to fool them into not pumping the rear of the car up. I am not sure where you can get the spacer from, but I do know that if you just buy the GC Kit, it comes with everything you need. I would highly recommend that option, that way you have all the adjustability you need.

I just picked up the spacer from another member - one of the mighty mouse ones.

I wasn't sure if the GC kit springs were the same as the Eibach Pro kit springs.

The car is currently riding on cut springs - with no spacers - and the shocks do not seem to be pumping. Is that normal? Note - I did not cut the springs, they came this way from the previous owner. He did 1.5 coils front and rear. It's really low, and I want something more manageable and uncut.

ctsv154
05-23-10, 03:45 PM
The springs that come with the GC kit are 2.5x10x(xxxlbs). You need the GC perches to use the straight 2.5x10 springs. The factory springs are much different. The standard Eibach lowering springs are basically a copy of a factory spring, just shorter. You can use the factory perches with those.

repenttokyo
05-23-10, 03:47 PM
thank you for the info - my search for actual eibach lowering springs will continue.

I have found a link to buy some here: http://www.ilovebodykits.com/product/40105/Eibach_Pro-Kit_Springs__-04_to_07_Cadillac_CTS-V_V8.html.

But people are telling me that the springs have been discontinued?

thebigjimsho
05-27-10, 06:29 PM
thank you for the info - my search for actual eibach lowering springs will continue.

I have found a link to buy some here: http://www.ilovebodykits.com/product/40105/Eibach_Pro-Kit_Springs__-04_to_07_Cadillac_CTS-V_V8.html.

But people are telling me that the springs have been discontinued?
Or just get the GC hardware. They may discount it for you without springs...

repenttokyo
05-27-10, 06:31 PM
Or just get the GC hardware. They may discount it for you without springs...

i'm not sure if i want to go with the GC kit. I've read mixed reviews.

tweeter81
05-27-10, 06:43 PM
Whatever mixed reviews you have read, it is far more worth it to have that adjustability. And you can't beat the price, the kit is dirt cheap!

Yes, I have had some minor noises (annoying, not scary) and you probably will too initially, but you just have to do your homework and fix them and then you'll be fine. All the noises are fixable by a non-mechanic, you just have to know what to look for. I highly recommend the kit for being 1/4 the cost of the other Coilover kits available for the V.

repenttokyo
05-27-10, 06:47 PM
I know that the kit is inexpensive, but the V isn't a track car for me - i already have one of those - so I am basically just looking for a reasonable drop, which springs will provide me in a much more cost-efficient manner.

The car is currently riding on cut springs, performed by the previous owner. It is very, very, very low, and I need to raise it up to something more reasonable, especially considering it will be winter driven.

The car already has a few annoying low speed noises with its current cut spring setup.

thebigjimsho
05-27-10, 06:54 PM
The GC setup can be completely trouble free if you just cover the bases on installation. If you ever decide to do that, we can help you. And it is an excellent kit for adjustability...

repenttokyo
05-27-10, 06:55 PM
would you say the ride / performance is better than the stock GM shocks and springs for everyday driving?

thebigjimsho
05-27-10, 06:59 PM
would you say the ride / performance is better than the stock GM shocks and springs for everyday driving?
I had a completely stock setup. Then I got FG2 shocks. Truth be told, the stock springs were a bad match for the upgraded shocks. The 500/550 GC setup proved to be a far better match and the ride was improved. The nice thing about the GC kit is that you can adjust the height and get custom spring rates and be as conservative or aggressive as you want...

RADARB8
05-27-10, 10:47 PM
What does GC kit stand for?:confused:

SkullV
05-27-10, 10:53 PM
What does GC kit stand for?:confused:

Ground Control. It is a kit that puts a sleeve over your front shock to make it a "coilover" and an adjustable perch on the rear spring. Great for a cheap adjustable setup.

thebigjimsho
05-27-10, 11:58 PM
It's track proven and time tested...

RADARB8
05-28-10, 02:55 AM
Ground Control. It is a kit that puts a sleeve over your front shock to make it a "coilover" and an adjustable perch on the rear spring. Great for a cheap adjustable setup.

That sounds like a good idea:yup:where can i purchase Ground Control..I'LL be doing some searching right now....also, i have the EIBACH'S on all 4 corners, and i have some negative camber issues in the front..the vehicle has about 27k miles on her and the insides of the tires were wearing badly..Not down to the cords or anything. just starting to get bald so i threw them out. in the meantime i bought off of EBAY an EIBACH KIT that helps to give the mechanic who is doing the front end alignment get rid of the neg. camber..it looks to be only 2 bolts. 1 for each side.. they are called ez cam or xr cam bolts...part#5.81260k/////has anyone ever used these EZ cam bolts or anyone know about them. :D thanks Greg

RADARB8
05-28-10, 03:06 AM
That sounds like a good idea:yup:where can i purchase Ground Control..I'LL be doing some searching right now....also, i have the EIBACH'S on all 4 corners, and i have some negative camber issues in the front..the vehicle has about 27k miles on her and the insides of the tires were wearing badly..Not down to the cords or anything. just starting to get bald so i threw them out. in the meantime i bought off of EBAY an EIBACH KIT that helps to give the mechanic who is doing the front end alignment get rid of the neg. camber..it looks to be only 2 bolts. 1 for each side.. they are called ez cam or xr cam bolts...part#5.81260k/////has anyone ever used these EZ cam bolts or anyone know about them. :D thanks Greg

Hey, i just found the link to GROUND CONTROL [gc] found out as u'll already know gc is Eibach....:banghead: still, i think for the fronts i should still use the camber bolts i bought......http://www.vividracing.com/catalog/ground-control-street-coilover-kit-bmw-m3-e46-0105-p-28442.html

repenttokyo
05-28-10, 10:16 AM
Hey, i just found the link to GROUND CONTROL [gc] found out as u'll already know gc is Eibach....:banghead: still, i think for the fronts i should still use the camber bolts i bought......http://www.vividracing.com/catalog/ground-control-street-coilover-kit-bmw-m3-e46-0105-p-28442.html

the GC kit uses eibach springs, but it is not the same as the eibach lowering kit you are using.

PISNUOFF
05-28-10, 10:44 AM
repent - you can buy the individual parts of the GC kit. I've purchased many replacement parts for a kit that I had that was incomplete. The Eibach lowering kit lowers the car a ton, probably comparable to removing the 1.5 coils that was done to your car. The GC kit with 500/550, either set of stock shocks and 3/4-1" drop is perfect and rides VERY similar to stock.

repenttokyo
05-28-10, 10:48 AM
A follow-up question. People seem to be using the 500 / 550 or 600 / 650 spring rates with the GC kit. What are the main differences in driving feel, and how much comfort is sacrificed going to the higher rate?

thebigjimsho
05-28-10, 11:40 AM
A follow-up question. People seem to be using the 500 / 550 or 600 / 650 spring rates with the GC kit. What are the main differences in driving feel, and how much comfort is sacrificed going to the higher rate?
I believe that since we use a sophisticated double wishbone suspension, we will never have a car that can crash hard like stiff setups on strut type suspensions. I think in a very basic sense, the 500/550 spring rate is the absolute best compromise for those that like comfort but still need to track the V once in a while. I used 500/550 springs on FG2s for a good few years and a number of track events and autocrosses.

I blew out an FG2 shock a couple of years ago. I now have T2 shocks which are much stiffer than FG2s and 650/700 springs. I did have QA1s and actually played with spring rates up to 900lbs. And they never crashed hard.

The T2 and 650/700 combo was only on the V for a week before I totaled it. But in that week I drove to Chicago from MA and was on my way back. And while they were firm, they were still long distance comfortable.

tweeter81
05-28-10, 12:56 PM
I believe that since we use a sophisticated double wishbone suspension, we will never have a car that can crash hard like stiff setups on strut type suspensions. I think in a very basic sense, the 500/550 spring rate is the absolute best compromise for those that like comfort but still need to track the V once in a while. I used 500/550 springs on FG2s for a good few years and a number of track events and autocrosses.

I blew out an FG2 shock a couple of years ago. I now have T2 shocks which are much stiffer than FG2s and 650/700 springs. I did have QA1s and actually played with spring rates up to 900lbs. And they never crashed hard.

The T2 and 650/700 combo was only on the V for a week before I totaled it. But in that week I drove to Chicago from MA and was on my way back. And while they were firm, they were still long distance comfortable.

I just recently switched out my 600/650 Eibachs with 750/800 Eibachs and they don't feel any different than the old setup. I am going to a track day this weekend and I am very interested to see how they feel on track compared to the old setup. I mainly made the switch because I was getting some rubbing on the rear 295s under high G turns, and am hoping that the stiffer springs cut down on the body roll that I do get (which is very minimal).

CadzillaTN
08-04-10, 09:12 PM
Or just get the GC hardware. They may discount it for you without springs...
they wont..


repent - you can buy the individual parts of the GC kit.
they say the parts are more than the whole kit..

I think I bought the springs tokyo was talking about.. eibach 2.5 id 500/550 springs from a GC kit. After researching the net for compatible perches with no luck and reading various threads, it seems these may be useless-- unless you guys have any suggestions or ideas to make them work?