CTS-V Suspension Tuning
09-13-2014, 07:58 PM
#142
Really? Because that's pretty much what you just did, one post earlier. And then when you're technically challenged, you change the subject. Why? Probably because you actually don't know much about cars. Otherwise, you'd respond with real insight and win the argument.
09-13-2014, 09:56 PM
#143
In REALITY my point is not to challenge you at all. I have tried your advice and as I said, I am not going to race my car, so your suggestion would not work for my needs, so I was working on another option for those that merely DD their car.
If you have anything else to say, please take it to PM.
Thanks.
If you have anything else to say, please take it to PM.
Thanks.
09-14-2014, 06:44 AM
#144
In REALITY my point is not to challenge you at all. I have tried your advice and as I said, I am not going to race my car, so your suggestion would not work for my needs, so I was working on another option for those that merely DD their car.
If you have anything else to say, please take it to PM.
Thanks.
If you have anything else to say, please take it to PM.
Thanks.
This thread should be called "Undamped CTS-V Suspension Tuning." Damper settings are a whole other subject and dramatically affect ride characteristics. For instance, the KW Variant 3 spring rates provided above will give you a fairly plush ride with compression damping set to full soft and rebound damping at 7 clicks and 5 clicks from full hard in the front and back, respectively. Add 3/4 turn of compression dampening to that setup, and the whole attitude of the car changes--now it's an autocross monster.
11-03-2014, 02:31 PM
#146
Not to add any fuel to a fire that has appeared to die but...
Don't the Nivomat shocks add to the spring rate? I know there are many variations of the Nivomat shocks but the factory uses 399 lbs/in springs in both front and rear. Given the suspension geometry this would make no sense if there weren't other factors affecting spring rate (keep in mind this car kicked butt on the Nürburgring long before anyone developed any aftermarket parts for it). Additional evidence to support this point:
The above is an excerpt from this link:
http://www.brakeandfrontend.com/nivo...control-units/
A link providing concrete demonstration (albeit with a different shock) that at least some Nivomats add to the spring rate.
http://volvospeed.com/vs_forum/topic...d-oem-springs/
So the information presented for the Ground Control setup is likely incorrect (unless someone is using the GC without any of the stock variant shocks).
However, this is still the best first cut approximation at suspension tuning for this car that I have ever seen. I wish someone with a copy of Wingeo would model the stock car and post the data so that all of us could benefit. That way we could make some fairly reasonable decisions about what we need in terms of suspension without trial and error and the resultant dropping a ton of money on useless parts.
Given all of the unknowns with FG2s I think I am about to take the plunge on new springs and dampers. Anyone interested in a GC setup with FG2s and MM spacers let me know.
Don't the Nivomat shocks add to the spring rate? I know there are many variations of the Nivomat shocks but the factory uses 399 lbs/in springs in both front and rear. Given the suspension geometry this would make no sense if there weren't other factors affecting spring rate (keep in mind this car kicked butt on the Nürburgring long before anyone developed any aftermarket parts for it). Additional evidence to support this point:
The Nivomat system does more than just level the vehicle under load. As the load increases, the pressure inside the shock increases as oil is displaced from the reservoir to the inside of the unit, compressing the gas volume. This creates a progressive increase in spring rate and damping with little or no change to ride frequency.
http://www.brakeandfrontend.com/nivo...control-units/
A link providing concrete demonstration (albeit with a different shock) that at least some Nivomats add to the spring rate.
http://volvospeed.com/vs_forum/topic...d-oem-springs/
So the information presented for the Ground Control setup is likely incorrect (unless someone is using the GC without any of the stock variant shocks).
However, this is still the best first cut approximation at suspension tuning for this car that I have ever seen. I wish someone with a copy of Wingeo would model the stock car and post the data so that all of us could benefit. That way we could make some fairly reasonable decisions about what we need in terms of suspension without trial and error and the resultant dropping a ton of money on useless parts.
Given all of the unknowns with FG2s I think I am about to take the plunge on new springs and dampers. Anyone interested in a GC setup with FG2s and MM spacers let me know.
06-03-2015, 09:50 AM
#149
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Finally pulled the trigger on these after my most recent track day pointed out the flaws in the stock setup.
I am still a little lost on what end links I need, and also what I should set the ride height at.
I am still a little lost on what end links I need, and also what I should set the ride height at.
06-03-2015, 01:03 PM
#150
TECH Enthusiast
The spring rates from KW are great, no need to change them especially if you street drive your car. they are very well balanced and maintains a very comfortable ride, actually more plush than stock, but also more controlled. I kept the stock swaybar endlinks because I wasn't sure if I was going to get new bars or not. The car handles so flat right now that I think I'm just going to keep them as is. I've pushed it pretty hard and haven't broke the stockers yet so i'll be keeping an eye on them.
07-12-2015, 04:49 PM
#152
Overall, as previously noted, no setup works for everyone and I will continue to try different spring rates, bump, rebound & height adjustments...
I've been running the KWv3 setup for quite a while (w/ their recommended bump & rebound settings) at the track with few problems but decided I wanted to see what stiffening up the rear end would do, so I replaced the KW springs with the 896lb Swift springs in the rear. I started with full soft compression & set rebound at 5 clicks from full hard as recommended earlier in this thread. (Running Team Dymanics 18x9 wheels with 245/45/18 slicks.) Results were pretty terrible (at Roebling)...
I wish I had run my KW setup there before to tell (maybe it was the track and I was over-driving) but stability control was turning on constantly when it normally only comes on for maybe 1 turn per track. No matter what I did with height or settings, I couldn't get it to calm down and felt like I was on marbles all day.
Also the 9" springs are about 1" shorter than the KW springs in the rear. That means the back was really low (two fingers between tire and wheel arch), even when I had the perches adjusted way up. Add really soft compression to that and, even with rolled rear fenders, I immediately chewed the outside of the driver's (not new) rear tire down to the cables. That was in part due to the track but in part due to contact w/ the inside of the wheel arch. I replaced the tires, increased the rear height and increased the compression to 3/4 turn and that did improve things a bit but the car still felt really slippery and did make some contact w/ the wheel arch.
I don't know if I'll go back to the KW setup or keep trying the 896lb with different compression and rebound settings. Regardless of that, I think it's odd that I had so much trouble with tires rubbing; it doesn't seem like others have had that much issue, even when they appear to be sitting with the tires tucked up inside the wheel arches.
I've been running the KWv3 setup for quite a while (w/ their recommended bump & rebound settings) at the track with few problems but decided I wanted to see what stiffening up the rear end would do, so I replaced the KW springs with the 896lb Swift springs in the rear. I started with full soft compression & set rebound at 5 clicks from full hard as recommended earlier in this thread. (Running Team Dymanics 18x9 wheels with 245/45/18 slicks.) Results were pretty terrible (at Roebling)...
I wish I had run my KW setup there before to tell (maybe it was the track and I was over-driving) but stability control was turning on constantly when it normally only comes on for maybe 1 turn per track. No matter what I did with height or settings, I couldn't get it to calm down and felt like I was on marbles all day.
Also the 9" springs are about 1" shorter than the KW springs in the rear. That means the back was really low (two fingers between tire and wheel arch), even when I had the perches adjusted way up. Add really soft compression to that and, even with rolled rear fenders, I immediately chewed the outside of the driver's (not new) rear tire down to the cables. That was in part due to the track but in part due to contact w/ the inside of the wheel arch. I replaced the tires, increased the rear height and increased the compression to 3/4 turn and that did improve things a bit but the car still felt really slippery and did make some contact w/ the wheel arch.
I don't know if I'll go back to the KW setup or keep trying the 896lb with different compression and rebound settings. Regardless of that, I think it's odd that I had so much trouble with tires rubbing; it doesn't seem like others have had that much issue, even when they appear to be sitting with the tires tucked up inside the wheel arches.
07-13-2015, 08:13 AM
#154
Staging Lane
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Belltech Muscle Car Coilovers (KW V3)
Sprint Rear 896# springs
Already Installed
Addco Rear Sway (Energy Suspension Greasable Mounting Brackets) Whiteline Lateral Limiters
Addco Front Sway (Rubs Stock Struts) - Hotchkis Mounting brackets and Whiteline Lateral Limiters
Banski Rear Shock Mounts
Sprint Rear 896# springs
Already Installed
Addco Rear Sway (Energy Suspension Greasable Mounting Brackets) Whiteline Lateral Limiters
Addco Front Sway (Rubs Stock Struts) - Hotchkis Mounting brackets and Whiteline Lateral Limiters
Banski Rear Shock Mounts
Last edited by SIGFOD; 08-25-2015 at 06:35 AM.
07-13-2015, 10:45 AM
#156
TECH Resident
although i will agree with you. the stiffer springs in the rear make it a bit more slide happy, but with the car properly aligned it sticks pretty good until i am in the throttle. pushing the gas will always make the tail end loose.
12-06-2015, 07:24 PM
#157
After breaking my lower ball joint and killing an FG2 I decided to take the plunge on the KWs. I went with the spring rates Fuzzy suggested (after running my weights and deciding the swifts Fuzzy used were the closest I could get). I also did the RevShift Red poly bushings up front while I was at it and put new Potenza RE71-Rs up front.
WOW!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
While I know that many have suggested these spring rates are too stiff, I have to say this is an awesome setup. It sticks the curves much better than my GC/FG2/MM setup. CREDIT WHERE CREDIT IS DUE. Fuzzy you got this one right.
Thank you!
WOW!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
While I know that many have suggested these spring rates are too stiff, I have to say this is an awesome setup. It sticks the curves much better than my GC/FG2/MM setup. CREDIT WHERE CREDIT IS DUE. Fuzzy you got this one right.
Thank you!
12-06-2015, 07:47 PM
#158
after I stiffened up the compression in the rear, I'm really happy with the KW + Swift spring + poly bushing combo as well. (The ultra soft compression Fuzzy suggested may be good for launches or daily driving but it wasn't what I was looking for.)
12-06-2015, 11:03 PM
#159
On The Tree
http://store.scalesuspension.com/col...e-cadillac-cts
Seen this in the other forum, and was wondering if this is something new, or just "relabeled".
(for whatever reason, the link doesn't work, but they show it in the INNOVATIVE SERIES)
Seen this in the other forum, and was wondering if this is something new, or just "relabeled".
(for whatever reason, the link doesn't work, but they show it in the INNOVATIVE SERIES)
Last edited by stick1975; 12-06-2015 at 11:12 PM. Reason: link didn't work
12-07-2015, 04:57 AM
#160
You have to remember when you replace a soft spring with a stiffer spring, you also have to adjust the rebound towards a harder setting.
Just adjusting compression is not enough.
I have rebound, compression and height adjustments on my ride. So when i get the height correct, i still have to adjust for compression and rebound.
Just adjusting compression is not enough.
I have rebound, compression and height adjustments on my ride. So when i get the height correct, i still have to adjust for compression and rebound.