Topic: Suspension upgrade

[roxer]

To the Kappa hive mind:

I ordered the DDMWorks brace bundle yesterday to start my suspension upgrade.  I have a few questions concerning the rest of what I want to do.  I have read much about GM upgrades for the LNF and from what I understand, I can upgrade the sway bars and springs to ZOK while keeping the stock shocks.  I see some are moving to BC coil-overs, but I personally like the stock shock option as I can work on it myself.

My questions revolve around change in height of the vehicle and ride quality.  I am assuming I have the two spring seats in the car at each shock from the factory.  Provided I leave them as is and install the ZOK springs, what height change am I most likely to see front and rear?  I think I read one say .5" all around - is that still correct after completely settling?  Is the ride that much harsher or a subtle change?

What am I to expect when I change out the sway bars handling wise and will it affect the ride?  Will I get more over-steer or under-steer with the bars?  Will the ride harshness increase?  I am assuming I will need an alignment after all of this.

Sorry for the millions of questions.  I want to make sure I do this once and make the right decision for me.

[wspohn]

The sway bars affect roll stiffness, not up and down motion so you won't see any added firmness in ride, just a lot less lean in corners.

I strongly suggest that you consider the BC Racing shocks if you are serious about suspension improvement.  A lot of bang for the buck, just as easy to service remove and replace as stock, and a lot more adjustment, including height.

[DaveOC]

To the Kappa hive mind:

My questions revolve around change in height of the vehicle and ride quality.  I am assuming I have the two spring seats in the car at each shock from the factory.  Provided I leave them as is and install the ZOK springs, what height change am I most likely to see front and rear?  I think I read one say .5" all around - is that still correct after completely settling?  Is the ride that much harsher or a subtle change?

The only way you'd have two spring seats on each shock is if your car had the Z0K option factory installed.  The second spring seat is there to increase the height of the car after the shorter Z0K spring is installed on the stock shock., for shipping clearance purposes.
.

[roxer]

The only way you'd have two spring seats on each shock is if your car had the Z0K option factory installed.  The second spring seat is there to increase the height of the car after the shorter Z0K spring is installed on the stock shock., for shipping clearance purposes.
.

Thanks for that information.  According to a few posts, I see that it did come with the Z0K upgrade only and required a second spring seat to be considered under warranty.  Down side is I cannot find the part numbers for the second seat front and rear?  I don't want to loose too much height as I scrape some entrances as it is now.  I was willing to live with .5" if that was the drop.  My intercooler is already a little close.    I'll continue to look and really would like to keep it as GM as possible, but BCs are now more of a reality as wspohn pointed out. 

[Sting Ya]

Another option that you may want to consider is a set of Koni Sport shocks/Struts especially for a street car .I have a couple of friends who autocross one has a Sky and they all said the same thing if you are going with coil overs a good set will run $1500.00 and up the lower priced sets are basically for people who want to lower their cars and lack the adjustment  features found on higher end units .The set up that I am currently installing on my car is Koni Sport Shocks/Struts  with Eibach Springs (lowered my car about an 1 1/2 " all the way around) complete DDM Works Brace kit ,Adjustable sway bars ,and polyurethane bushings Again it all depends on what you are looking to get out of the car I just want a great handling street car.

[LatinVenom]

I have the ZOK setup and it lowers the car .75 all the way around.
I have both sway bars and the shock/springs.

[Gentleman Jack]

I'm not sure if this is the right thread for this but...

I'm sitting in the PHX airport with a 2.5 hour layover. I've challenged the bartender to make Rye drinks I've never had. So far I'm up 2-0
He must be an amateur. He started with a Manhattan and went to an Old Fashion. Does he think I'm a ROOKIE?

[roxer]

I have the ZOK setup and it lowers the car .75 all the way around.
I have both sway bars and the shock/springs.

Is the ride as harsh as some say with the Z0K gear installed?

I'm not sure if this is the right thread for this but...

Sure, as long as you are putting them down, type while you can...    

On another note, I would like to confirm this is the spring seat that needs to be added.  Found this on CED:

http://www.crateenginedepot.com/Spring-Spacer-15917514-P17489C683.aspx

Will this keep the car at stock ride height with the Z0K springs?

[Robotech]

I strongly suggest that you consider the BC Racing shocks if you are serious about suspension improvement.  A lot of bang for the buck, just as easy to service remove and replace as stock, and a lot more adjustment, including height.

I just recieved my suspension upgrades yesterday and I ordered the BC shocks. These things are beautiful...shame you won't be able to see them on the car. I'll be putting them on this weekend and will report back how the entire upgrade changes the feel of the car from stock.

[Critterman]

I ended up with the ZOK suspension which is a lot softer that what I started with.

[wspohn]

Anyone interested in the BC Racing shocks should read this thread:

http://www.kappaperformance.com/forum/index.php/topic,1638.msg17222.html#msg17222

Beautifully made, and the equal of shocks costing 1.5 - 2.5 X as much.  They are available usually around $1,000 a set of four, including springs.
 
See for example http://www.ddmworks.com/SolsticeSky-BC-Coilovers_p_52.html

[kwtoxman]

Anyone interested in the BC Racing shocks should read this thread:.......... Beautifully made, and the equal of shocks costing 1.5 - 2.5 X as much.

I don't know how someone can say that with a straight face. Fine though, as everyone is entitled to their opinion.

Internet research shows a weight of evidence that contradicts that statement. They are not equal. The more expensive shocks with added adjustability are better and worth it for people who want/need that. That is why BC makes the ER option as well, which is not cheap and better compares to the more expensive suspension options.

Also, if a person drives in all kinds of weather or year round, some of the more expensive options have better corrosion resistance and are worth it to some buyers. It's amazing how much corrosion that area can see when driven through all weather.

The cheaper BC series is a great option for a basic SA upgrade. A quality coilover at a good price. And there are a variety of other options out there that can be worth it to buyers, depending on wants/needs.

[Sol Asylum]

The cheaper BC series is a great option for a basic SA upgrade.

I'm perfect the way I am, I don't need any upgrade.  Even if I did it wouldn't be cheap!

[wspohn]

I don't know how someone can say that with a straight face. Fine though, as everyone is entitled to their opinion.

Would I use them on a race car? No. But for the street, the results you will get will be pretty much as if you had put on the more expensive shocks.  The 0.1% that actually do  run in competition should go out and get a set of double adjustable.

The BR series give you the same thing at $1,000 as the KW-1 does for $1550.  The ER will cost you another $800 or so, but are still less than the equivalent 'other' shocks, usually around $2200.

You buy whatever level of shock you need or want, but the point is that the BC product is excellent and considerably less expensive at whatever level you opt for.  There are too many crap shocks produced in the Far east, and it makes people think twice when you tell them these are made in Taiwan, but they are a quality part at a bargain price.

[kwtoxman]

Would I use them on a race car? No. But for the street, the results you will get will be pretty much as if you had put on the more expensive shocks.  The 0.1% that actually do  run in competition should go out and get a set of double adjustable.

Buying suspension is about more than just "results" to most people. People tend to consider many things when purchasing. Plus people have different values and judgements that they apply, so what one person makes for a decision may not be the case with another person. As such there is no right answer and people can be equally correct and justified in buying a more expensive coilover if they think it is worth it for them. As correct as you are to think that the cheaper BC coilover is best for you.

I find that many people who upgrade their coilovers run in competition, which would be a much more appropriate stat to consider (and much higher number) than the one given. And besides that,  as just mentioned, choosing a coilover about more than running in competition for most people. 

The BR series give you the same thing at $1,000 as the KW-1 does for $1550.  The ER will cost you another $800 or so, but are still less than the equivalent 'other' shocks, usually around $2200.

They give you the same thing? Maybe you are referring to similar "results" since you focused on that earlier, but again, there are other differences between the BR coilovers and the KW V1 coilovers that can be considered by people. And everyone too is entitled to their own value judgements, opinion and choice.

And instead of comparing what is a discount price to MSRP which inflates the price gap, let's look at what a supporting vendor can do.
E.g.,
$1025 http://www.ddmworks.com/SolsticeSky-BC-Coilovers_p_52.html
$1350 http://www.ddmworks.com/SolsticeSky-KW-Variant-1-Coilovers_p_108.html
$1935 http://www.ddmworks.com/SolsticeSky-KW-Coilover-Variant-3_p_107.html

[elff]

Another option that you may want to consider is a set of Koni Sport shocks/Struts especially for a street car .I have a couple of friends who autocross one has a Sky and they all said the same thing if you are going with coil overs a good set will run $1500.00 and up the lower priced sets are basically for people who want to lower their cars and lack the adjustment  features found on higher end units .The set up that I am currently installing on my car is Koni Sport Shocks/Struts  with Eibach Springs (lowered my car about an 1 1/2 " all the way around) complete DDM Works Brace kit ,Adjustable sway bars ,and polyurethane bushings Again it all depends on what you are looking to get out of the car I just want a great handling street car.

I 100% disagree with this.  I had both Koni's and Eibach springs and hated them.
The problem with the Eibachs is two fold.
1. They don't understand our vehicles.  They actually think the solstice has a different suspension than the sky.
2. Their spring rates are backwards.  All GM Spring combos have the rear's being stiffer than the fronts.

Eiback does not realize how good the weight balance of our cars is and thinks the fronts need to be stiffer to support the weight of the engine.   They are wrong.

Here is a good comparison of a lot of options out there for the Kappa's that details the above statement.  Take a look at how every GM combination whether NA or Turbo has the rear's stiffer than the front. 

http://www.kappaperformance.com/forum/index.php/topic,8724.0.html

As far as the Koni's goes, they worked extremely well for Autocross, but IMHO they sucked on the street.  They don't respond quick enough.  The 5 different settings just change how they react.  You either bottom out, or you skip across the surface. Neither give you optimum tire contact.

For the same reasons as the Eibachs, I am not a fan on Unmodified KW's.  The rears have a lower spring rate than the fronts.  You need to add stiffer springs to the rears of the KW's which is even more cost.

I would suggest going with the ZOK springs and FE3 shocks. The Solstice won the T2 class repeatedly with that combination and you have to ask yourself, are you a better driver than the guy who raced the T2 winning car?

I've actually had and driven 5 different suspension setups on my Sky and have a lot of experience with how each shock/spring combination behaves on our cars on kind of crappy PA roads. 

My favorite to date was the GMPP setup for the Sky. 
http://www.crateenginedepot.com/Off-Road-Shock-Absorber-Package-17800029-P12618C683.aspx
The shocks respond slightly better than the FE3s and the spring rate of the springs is the same as the ZOK's. The problem is you can't buy the shocks alone. So if one fails you have to re-buy the whole kit.   As such, the next best option for a street vehicle is adding the ZOK springs to your existing FE3 shocks and it's also a pretty cheap option.

Here is a direct link to the Front Springs you want
http://www.crateenginedepot.com/FE3-LNF-ZOK-Front-Spring-25849163-P10874C683.aspx

Here is a direct link to the Rear Springs you want
http://www.crateenginedepot.com/FE3-LNF-ZOK-Rear-Spring-25855626-P10875C683.aspx

That is from our Forum Sponsor Shop GM Accessories.com
[The website redirects to their old name still]

[roxer]

Thanks all for the ton of experience and knowledge. Watching the give and take from veterans is very informative and helped with my options.  I like the Z0K option because I can do a lot of it myself. I can easily replace the shocks from various sources - and hopefully for a long time to come. The upgrade was designed for the car. Downside is the drop in height.

I do like the cost of the BC option and the ability to set ride height. My concern is future shock replacement availability unless it means a total replacement for shock and spring. I am hoping I can run a second spring seat and keep close to the same ride height. What can I expect if I do run the second seats on the Z0K springs?

[elff]

The second spring seat was so the solstice could progress through the assembly line

Im my case, the sky dropped less than an inch with new zok springs.  Since the car was kind of on the high side with the stock springs,
I consider it at the height it should be now

[Sol Asylum]

Must not make Elff height joke.

[roxer]

I guess another benefit would be having a Z0K setup for an NA when I get one. That is correct, right?  The Z0K stuff for an NA is basically the FE3 suspension for the GXP?

So there are no problems with running the second seat if I wanted?

[roxer]

Must not make Elff height joke.

Shear will, huh?

[Sting Ya]

I have used this combination ( Konis & Eibachs) on a few of my cars and it has worked well for me I like the quality of both products and the performance that I get out of them . I am not an autocrosser ,roadracer or suspension engineer just guy who enjoys driving his car on the twisty country roads near my house . That being said what may be right for me may not be right for some else that's why you have to find what works for you and if you do stick with it.

[Sol Asylum]

Shear will, huh?

just that it's Critters turn

[kwtoxman]

I 100% disagree with this.  I had both Koni's and Eibach springs and hated them.
The problem with the Eibachs is two fold.
1. They don't understand our vehicles.  They actually think the solstice has a different suspension than the sky.
2. Their spring rates are backwards.  All GM Spring combos have the rear's being stiffer than the fronts.

Eiback does not realize how good the weight balance of our cars is and thinks the fronts need to be stiffer to support the weight of the engine.   They are wrong.

Here is a good comparison of a lot of options out there for the Kappa's that details the above statement.  Take a look at how every GM combination whether NA or Turbo has the rear's stiffer than the front. 

http://www.kappaperformance.com/forum/index.php/topic,8724.0.html

As far as the Koni's goes, they worked extremely well for Autocross, but IMHO they sucked on the street.  They don't respond quick enough.  The 5 different settings just change how they react.  You either bottom out, or you skip across the surface. Neither give you optimum tire contact.

For the same reasons as the Eibachs, I am not a fan on Unmodified KW's.  The rears have a lower spring rate than the fronts.  You need to add stiffer springs to the rears of the KW's which is even more cost.

To fully characterize it, KW increases the front and rear spring rate on the solstice options over stock (non-Z0K), but the rear rate is not increased as near as much as the front. The result is the front spring rate is higher than the rear spring rate.

Spring rates are about a lot more than weight balance. FWIW there are people with other cars running aftermarket suspension with higher front spring rates than rear  (e..g, doing some internet research shows similar cars such as S2000's, BRZ's, Miata's and other front engine rear wheel drive cars).

Doing some reading, one sees that there are lots and lots of varying opinions on selecting spring rates, and if any conclusion can be drawn (that a few people have pointed out) it is that there is no correct single answer or set-up. Many variables will impact selection of F/R spring rates, including driving environment, driving style and preferences.

This link shows how much spring rates can vary based upon driving environment, from higher front spring rates in AX to higher rear spring rates for the track.

AutoX priorities:
- lightning fast weight shifts and small direction changes (less than 30 degrees). This is for slaloming.
-- This is achieved by REALLY high front spring rates, and a giant front sway
-- This also makes it so that under sustained cornering (sweepers), the car pushes like CRAZY, so that's why AutoX cars go deep, brake hard, and power out, rather than make a more rounded arc.

Track priorities:
- Sustained cornering speed, and being able to put power down at corner exits
-- This is achieved by getting a nice static balance.
-- Keep in mind that under power, you're unloading the front, and loading the rear.
-- Track prepped cars will sustain more raw cornering Gs, but not change direction and shift weight as quickly.

AutoX prepped FRS
- 14k/9k spring rates
- Blade type front sway, minimal rear sway

Track prepped FRS
- 10/12k spring rates
- Sways to fine tune balance.
http://www.ft86club.com/forums/showpost.php?p=1482922&postcount=18

I'd be interested in hearing why you think a higher rear spring rate is needed on the solstice, handling-wise. Unless going for bone jarring ultimate performance with high spring rates and calculating NFs, typically increasing the rear spring rate is done if bottoming in use, or as a way to get more oversteer or less understeer. I don't have any problems with either of those things and in fact I need to dial out a bit of tail-happy oversteer in my AX use. I wouldn't mind trying a higher rear spring rate at some point to see how it works for me, and if I AX more I hope to. For now, the car is a reasonable compromise of street/AX usability. The nice thing is that with a DA shock, there is typically enough range to be able to play with reasonable spring rates without any negative effects.

Bottom line is that a lower rear spring rate can be a valid set-up on certain cars including the solstice for some people, especially in a combo street/AX car, others prefer a higher rear spring rate for various reasons (track, feel, driving style, etc).


Here is a link I found helpful - a general guide to suspension changes and what it affects, plus recommended adjustments to fix handling issues.
http://www.trackhq.com/forums/f295/effect-suspension-changes-494/

I would suggest going with the ZOK springs and FE3 shocks. The Solstice won the T2 class repeatedly with that combination and you have to ask yourself, are you a better driver than the guy who raced the T2 winning car?

The Solstice GXP winning the T2 national championship did not have Z0K springs and FE3 shocks. lol. And for that matter, any national champion winning solstice in any class (and any other car for that matter) is not running stock manufacturer supplied coilovers or springs. 

Don Knowles, took his Pontiac Solstice to the 2009 T2 National Championship on ANZE Suspension. Andy Wolverton finished third, running a similar suspension setup from ANZE on his Solstice. http://www.anzeengineering.com/scca-road-racing/2009-scca-run-offs-t2-another-national-championship/

Also, T2 is a road course, which as discussed earlier is a notably different suspension set-up than autocross.

[elff]

Yes
The T2 course is more similar to what you will experience on the road.
Our suspension and car is not like other cars.  When you attempt to use that logic it results in a bad riding vehicle.

My experience is not based on internet research, it is based partially on how GM engineers designed the car and how all of their setups are done for street, T2 AND Autocross, all of which are detailed in the their solstice setup book
Combined with
Having personally installed and tested them.   The real world experience completely backs up what the GM engineers put together.
DDM dave also posted at one time that they put stiffer springs on the rears of their KWs to increase the handling of the soltice they were using