: GC: 500F/550R vs 600F/650R



rand49er
12-20-06, 05:24 PM
Thanks to another member here, I made the swap today to the stiffer setup.

Yes, it's stiffer. No, it's not dramatic. Yes, it could very easily be a daily driver. And yes, I love it! :bouncy:

With the exception of not having FG2s, this is the way the car should have rolled off the assembly line. Bumps are very tolerable, and cornering is flat and with purpose. Someone (maybe Chef?) was talkin' about 750F/800R, and I could see that setup working very well indeed. Guys/gals, this GC setup is nice. Anybody on the fence should just do it. :D

(BTW, I knew before that I wasn't a mechanic, and thank goodness I'm not working as such. When I had installed the GC originally, I left the five bolts holding the upper control arm/shock mount assembly LOOSE (driver side), and I mean LOOSE! Holy crap, I'm glad I hadn't driven it much since then. Sometimes I do some really bonehead things. :thepan:)

Seattle CTS-V
12-20-06, 06:55 PM
Someone (maybe Chef?) was talkin' about 750F/800R, and I could see that setup working very well indeed.


I have the 550F/600R setup right now and wish I had gone stiffer. The car still has a noticable sway...though I believe too stiff could decrease weight transfer and lessen traction?? I'm thinking that the 600/650 won't meet my expectations though and would love to hear if a 750/800 improves track performance or kills it.

Chef
12-21-06, 02:06 AM
I have the 600/650's and am thinking Penske or 700's for sure - When we go this fast and the shear weight on road courses I still feel the body shift which just assists the rear gettin' loose.

I went on a trip with an unamed car club here and drove to Payson from Scottsdale going 125-145 through curves and sometimes would get the oh shhhhhiat almost lost it feeling. Tight suspension is the only way for extreme speeds and cornering in this car.:alchi:

Chef

rand49er
12-21-06, 07:37 AM
Having now experienced the 600/650 setup, I really think that the 700+ springs will not only be better at those high speeds but still be acceptable as a DD.

125-145 and on curves no less ... :eek: !

Chef
12-21-06, 10:07 AM
Having now experienced the 600/650 setup, I really think that the 700+ springs will not only be better at those high speeds (http://www.cadillacforums.com/forums/#) but still be acceptable as a DD.

125-145 and on curves no less ... :eek: !

Don't get me wrong these coilovers are nice but just need to be tighter. The curves were the slight bending curves through mountains not sharp twisties but still made me feel it:alchi:

lunarx
12-21-06, 10:47 AM
Chef, what shocks do you have?
With the weight our cars need to manage at each corner I can see how extra firmness in the suspension would be a good thing.
I just never imagined such drastic changes from the stock spring rates would be needed.
Perhaps it's the shocks that need improvement.

Feffman
12-21-06, 12:04 PM
I have the 600/650's and am thinking Penske or 700's for sure - When we go this fast and the shear weight on road courses I still feel the body shift which just assists the rear gettin' loose.


Chef:

Has anyone heard anything from Penske about their suspension set up?
I dropped them an e-mail about two weeks ago and still no answer. I figured they may not be interested in selling the shocks/springs set up.

Feff

Chef
12-21-06, 12:05 PM
That's why Penske may be getting a call or these Sachs racing? coils are most likely not the end all for sure - It's definetely a combo -

rgd
12-21-06, 04:58 PM
Thanks to another member here, I made the swap today to the stiffer setup.


Someone (maybe Chef?) was talkin' about 750F/800R, and I could see that setup working very well indeed.

That woulld be me!
Sometimes I do some really bonehead things. :thepan:)

And, that would be me!

Which brings me to a post I started yesterday then pushed the wrong button and, wammo it was gone. Yes 750/800 springs are stiff but I am sure they will work well on the track. I will know sometime Sat morning after my second session at Laguna. I don't care to be one of the guys that spins on the first session. Happens every time out!

Anyway about the post I was/am going to do. I will post a new thread because it is worthy of the attention (I think) so others don't do this :banghead: to themselfs as I did.

Thanks,
rgd
thread will be titled "Hotchkis/Ground Control/Endlink" 101 or Endlinks for Dummies

Feffman
12-24-06, 11:55 AM
Chef:
Has anyone heard anything from Penske about their suspension set up?
I dropped them an e-mail about two weeks ago and still no answer. I figured they may not be interested in selling the shocks/springs set up.


Penske? Penske? Has anyone heard from Penske?

Feff :annoyed:

Chef
12-24-06, 01:38 PM
Penske? Penske? Has anyone heard from Penske?

Feff :annoyed:

Also - more info on those racing Sachs too?

rgd
12-25-06, 01:06 AM
FYI... 750/800 awsome! Honestly not at all bad as my daily driver set either.

Kingpin08
03-15-08, 12:41 AM
on Ground Control's website, would the street performance be 500/550, the hot rod caddy be 600/650, and the autox-track day be 750/800?

thebigjimsho
03-15-08, 01:01 AM
I have 500/550 and I find that to be the perfect mix of street and track...

trukk
03-15-08, 06:17 PM
I have 500/550 and I find that to be the perfect mix of street and track...

Jim is a wussie though :stirpot:

-Chris

type911
03-15-08, 07:30 PM
I also have 500/550 on the way. I think for me its wise do to the size of the sinkholes the state of MA calls potholes.

thebigjimsho
03-16-08, 06:02 PM
Jim is a wussie though :stirpot:

-ChrisYou were wishing you had wussie springs as you faded to Bolivian...

rand49er
03-16-08, 06:15 PM
... street performance be 500/550, the hot rod caddy be 600/650 ...Had 'em both and didn't think there was a vast difference. Some difference, yes. Vast ... no.

How's that for subjectivity. :rolleyes:

atdeneve
03-16-08, 10:49 PM
on Ground Control's website, would the street performance be 500/550, the hot rod caddy be 600/650, and the autox-track day be 750/800?

Unless Ground Control changed their initial offerings, the highest springs available were 600/650. The three options being 500/550, 550/600, and 600/650.

Unless you have heavy duty aftermarket shocks, the 600/650 spring rates were the highest they recommended. That's for the FG2 shocks. FE4 shocks would be lower.

You may need to get a stiffer set of shocks if you were to go higher in spring rate. RGD had QA1 adjustable shocks mated to his 750/800s.

Kingpin08
03-17-08, 01:23 AM
I was curious because I am about to order a set. So which spring rates would I be getting for the street performance, hot rod caddy, and track day drop down menus?

thebigjimsho
05-31-08, 03:00 PM
Just a bump for Justin...hope this helps...

type911
05-31-08, 04:51 PM
I have a question. I have the front springs wound all the way up yet still feel it is too low. I have no where else to go on the adjustment dial. 500/550 springs. What could be the problem? I have moved the dial up the sleeve by 1.5 inches but see no change in ride height.

PISNUOFF
05-31-08, 08:31 PM
I have mine set about 3/8" from the top of the adjustment and I rub over bumps. I have the 500/550 and FE4's but I also have 255/55's which are 10 mm larger in diameter than stock. I'm either going to raise the front up the extra 3/8" or install RGD's QA1's and heavier springs that I purchased from him. For now I just have them sitting in the basement needing to be rebuilt.

Twitch
05-31-08, 09:37 PM
I have mine set about 3/8" from the top of the adjustment and I rub over bumps. I have the 500/550 and FE4's but I also have 255/55's which are 10 mm larger in diameter than stock. I'm either going to raise the front up the extra 3/8" or install RGD's QA1's and heavier springs that I purchased from him. For now I just have them sitting in the basement needing to be rebuilt.

255/55 are kinda huge. Sure you don't mean 255/45? I ask because I have 255/45 with FE4s, and I'm getting a GC kit soon. I'll probably go with the medium springs, but its really bumpy here in NYC.

Tony

rand49er
06-01-08, 11:05 AM
Tony, reconsider the 600/650 setup. It's honestly not that much stiffer, and you can go smidgeon lower without bottoming out. I appreciate anyone not wanting to drive over crap roads with a stiff suspension, however.

I had a picture of my car parallel parked behind a regular CTS as viewed from across the street from a year ago. It really put the looks of the lowering into perspective with that comparison ... really nice! Just looked and couldn't find it, though :rant2: or I'd post it up here.

Twitch
06-01-08, 12:57 PM
Tony, reconsider the 600/650 setup. It's honestly not that much stiffer, and you can go smidgeon lower without bottoming out. I appreciate anyone not wanting to drive over crap roads with a stiff suspension, however.

I had a picture of my car parallel parked behind a regular CTS as viewed from across the street from a year ago. It really put the looks of the lowering into perspective with that comparison ... really nice! Just looked and couldn't find it, though :rant2: or I'd post it up here.
This is actually a tough one for me. I'm ready to buy it, and it'll probably be the 600/650 combo, or 550/600 if they offer that. Just a few things I have to think about.
I thought about upgrading the shocks also since it wont be any more work to do so. I think I'll hold off on the shocks cuz they take $1000 away from my engine "weight" mod. :)
I guess I'll just do the work over again when I get new shocks. Little worried on how hard the suspension will be then. As it is, I worry about the car rattling because the crappy roads I drive on.
I fully understand that you cant have the best of both worlds, and I'll take a rough ride with the better performance. But you do have to draw a line somewhere, so you still enjoy driving the car, and keep it in one piece.
I'm gonna just go with the stiffer springs, and take it from there.

BTW how did the FG2s affect your ride?
Thanks

Tony

thebigjimsho
06-01-08, 02:42 PM
This is actually a tough one for me. I'm ready to buy it, and it'll probably be the 600/650 combo, or 550/600 if they offer that. Just a few things I have to think about.
I thought about upgrading the shocks also since it wont be any more work to do so. I think I'll hold off on the shocks cuz they take $1000 away from my engine "weight" mod. :)
I guess I'll just do the work over again when I get new shocks. Little worried on how hard the suspension will be then. As it is, I worry about the car rattling because the crappy roads I drive on.
I fully understand that you cant have the best of both worlds, and I'll take a rough ride with the better performance. But you do have to draw a line somewhere, so you still enjoy driving the car, and keep it in one piece.
I'm gonna just go with the stiffer springs, and take it from there.

BTW how did the FG2s affect your ride?
Thanks

TonyAs a fellow Northeasterner, let me share my thoughts. For all the go fast mods one does, a few handling and braking mods will well outweigh a moderate amount of power mods on a road course. The $6G worth of power mods that may have gotten you 3-4 car lengths down the back straight at Shenandoah, just was made up, and surpassed, by $600 slicks, $200 brake pads, $500GC and $1G FG2s...

If you are thinking of GC, do the FG2 at the same time and save a few hundred bucks. The FG2 are too stiff for stock springs. They give you impact harshness and the wallow of a softer spring. The GC will most likely be too stiff for the softer stock struts. The FG2 should work well with the 500/550 to 600/650. But I am perfectly happy with the 500/550 and FG2 both at the track and on New Englands potholed and frostheaved roads...and NYC is worse...

PISNUOFF
06-01-08, 07:08 PM
255/55 are kinda huge. Sure you don't mean 255/45? I ask because I have 255/45 with FE4s, and I'm getting a GC kit soon. I'll probably go with the medium springs, but its really bumpy here in NYC.

Tony

Sorry Tony, I meant 45. Also, if you're going to upgrade to FG2's, you might as well do it now because when you do, you'll need new GC components due to the outer diameter of the FE4's being different from the FG2's.

lilred
06-01-08, 09:08 PM
My car came stock with FG2's. What is involved in installing the GC 500/550 set? Is this a DIY in your garage kinda thing? Which supporting vendor sells the kit anyway?

psycho43142
06-01-08, 09:17 PM
How much stiffer if any are the QA1's over the FG2's, I AX alot and right now have the FE4's and am going to upgrade later this Summer and was just trying to gather as much information as possible before I decide which way to go. Another question, besides those 2 are there any other options besides some custom builds from someone like Brenner Fabrication?

Chris

Twitch
06-01-08, 09:28 PM
My car came stock with FG2's. What is involved in installing the GC 500/550 set? Is this a DIY in your garage kinda thing? Which supporting vendor sells the kit anyway?
The FAQ has the install instructions, and you can google "Ground control" to get the website.


How much stiffer if any are the QA1's over the FG2's, I AX alot and right now have the FE4's and am going to upgrade later this Summer and was just trying to gather as much information as possible before I decide which way to go. Another question, besides those 2 are there any other options besides some custom builds from someone like Brenner Fabrication?

Chris
I thought the QA1s were adjustable. That's both good and bad. Its great if you know what your doing, but can be a pain in the a$$.
You can dial it in great on one road, but it'll suck on another kind of road. In the end, it'll still be a compromise. Just mu opinion though.

Tony

Twitch
06-01-08, 09:38 PM
Just tried to order my GC kit. Stupid shipping policy, they only deliver to billing addresses :rant2:
Now I gotta call them and set something up.

PS stupid me thought it was the same kit for both FE4 and FG2. Really didn't wanna spend the extra cheddar yet :helpless:

rand49er
06-02-08, 08:44 AM
... PS stupid me thought it was the same kit for both FE4 and FG2. Really didn't wanna spend the extra cheddar yet :helpless:Tony, not sure what PISSIN' (<-- j/k) was referring to. I did the GC kit with my FE4s and drove like that for over a year (though no racing/tracking/etc). Got FG2s from Luke around Thanksgiving and installed them in December during a brief lull in the global-warming-induced-freezing winter we had here in SE Mich. It was a pretty straightforward swap. :confused:

type911
06-02-08, 11:14 AM
So the kit is not FE4 FG2 specific?

Twitch
06-02-08, 11:24 AM
So the kit is not FE4 FG2 specific?
Talked to Randy, he used the same kit on both shocks.
I'll talk to someone at GC, but I'd like to get some more feedback here before I take their word for it.
I know the FG2s are wider, but maybe that has nothing to do with it.
Also, isn't it a direct swap between FE4 and FG2, with stock springs? I'll check the FAQ on that one.
Thanks

Tony

Twitch
06-02-08, 08:59 PM
Just got off the phone with GC. They said its the same kit for both shocks.
They can do any combination you ask for. I might go with 550/600. Hopefully that won't be too harsh, and it'll hold me over till I can get the FG2s.
Couple more things to look into, and I should order them in the next day or two.

Tony

thebigjimsho
06-02-08, 09:05 PM
Just got off the phone with GC. They said its the same kit for both shocks.
They can do any combination you ask for. I might go with 550/600. Hopefully that won't be too harsh, and it'll hold me over till I can get the FG2s.
Couple more things to look into, and I should order them in the next day or two.

TonyUnless you want to lower your V when you want to, I don't see the benefit of getting coilovers without the struts to match up. I don't think your handling benefit will be quantifiable until you do. I think you're better served to wait for the struts and save on the install.

thebigjimsho
06-02-08, 09:06 PM
But if you really want to, by all means do it! It's just my own $.02 based on what I wish I did...

Twitch
06-02-08, 10:53 PM
But if you really want to, by all means do it! It's just my own $.02 based on what I wish I did...
I kinda enjoy the work, but yeah, nobody wants to do the same thing twice. :banghead:
I have no answer for you. Its just the mod bug......
Don't worry though, I have a bunch of excuses to make myself feel better :sneaky:

PISNUOFF
06-04-08, 03:50 AM
Tony, not sure what PISSIN' (<-- j/k) was referring to. I did the GC kit with my FE4s and drove like that for over a year (though no racing/tracking/etc). Got FG2s from Luke around Thanksgiving and installed them in December during a brief lull in the global-warming-induced-freezing winter we had here in SE Mich. It was a pretty straightforward swap. :confused:

Sorry, my dumba$$ was probably thinking about my QA1's and FE4's. I will try not to open my mouth anymore when I'm not sure (probably not any less either).:bang2:

rand49er
06-04-08, 07:38 AM
... I will try not to open my mouth anymore when I'm not sure (probably not any less either).:bang2:What? And be the only one?

Done it many times myself. At least I can blame it on age. :rolleyes: