Topic: Sky/Opel has more suspension travel than Solstice

[kennysabarese]

Check this YouTube clip, I didn't realize that there was a difference. Does anyone know what parts would affect this?

[Imaj]

I wish he would have asked why they did not put a roll bar in the car.

[LiquidPT]

Check this YouTube clip, I didn't realize that there was a difference. Does anyone know what parts would affect this?

I had heard the Sky had a cushier suspension. Don't know if it's just in the base models, or if it's in the RL/GXP as well.

[kennysabarese]

I have been asked by several people to clarify which parts make up which of the suspension levels.  Here is a compilation of this information, with spring rates and loads.

I hope people understand what a check height and check load mean for a spring.  The check height is not the same spring length as any particular loading.

Some definitions:
LE5 = Base naturally aspirated 2.4l engine
LNF = 2.0l turbo SIDI
SDT = Street Edition
FE2 = the option code for the base suspension
FE3 = option code for uplevel suspension

You will notice that the SKY LE5 front spring has a higher load.  In general, the SKY is slightly heavier due to option content, differences in structural mass, etc. and requires a slightly higher load spring to keep the trim height in specification.

Code: [Select]

Application               Front Spring                Rear Spring
                          Frt Shock    (chk ht. =         Rear Shock    (Chk ht. =     
                   211.5mm)               217.5 mm)
=====================================================================================================

FE2 LE5 Solstice    15278695*    15244327        15278696*    15280026
2006 MY            Code 9??*    (3600N - 22.5 N/mm)    Code 9??*    (3700N - 31.0 N/mm)     
                   [Tag = Lt Grn]               [Tag = Tan]
=====================================================================================================
FE2 LE5 Solstice    15224875    15244327        15236924    15280026
2007+MY            Code C404    (3600N - 22.5 N/mm)     Code C406    (3700N - 31.0 N/mm)     
                   [Tag = Lt Grn]               [Tag = Tan]   
=====================================================================================================
FE2 LE5 SKY        15224875    10376421        15236924    15280026
            Code C404    (3800N - 22.5 N/mm)     Code C406    (3700N - 31.0 N/mm)     
                   [Tag = Dk Grn]               [Tag = Tan]   
=====================================================================================================
FE3 LNF (Non Z0K)    15901220    15784872        15901221    25787858
(All Non-Z0K LNF Kappa)    Code C646    (3800N - 30.5 N/mm)     Code C648    (3900N - 40.0 N/mm)   
                   [Tag = Brown]               [Tag = Purp Stripes]   
=====================================================================================================
LE5 Z0K Solstice    15901220    15906534        15901221    15906532
also Street Ed. SDT    Code C646    (3100N - 30.5 N/mm)     Code C648    (3250N - 40.0 N/mm)     
                   [Tag = Lt Grn Stripes]            [Tag = Lt Blu Stripe]   
=====================================================================================================
LNF Z0K Solstice    15901220    25849163        15901221    25855626
            Code C646    (3100N - 37.0 N/mm)     Code C648    (3200N - 50.0 N/mm)   
                   [Tag = Orange Stripes]            [Tag = Yellow Stripe]   
=====================================================================================================
GM SPO Perf Parts    88965295    88965293        88965296    88965294
            Code C388    (3450N - 37.0 N/mm)    Code C390    (3350N - 50.0 N/mm)   
                   [Tag = White]               [Tag = Lavender]   
=====================================================================================================

* The 2006 Solstice had a different shock valving and shorter jounce bumper with a different rate progression.
The 2007 FE2 SKY, introduced early 2006, had a revised jounce bumper and a better shock valving to work with the new jounce bumper.
This was well-received, so the changes were rolled into the FE2 Solstice in 2007 model year and parts commonized.
The 2006 shocks are not available in service, both old and new jounce bumper are available in service.
2006 Solstice are all FE2 and all have the 15159045 jounce bumper.  All 2007+ kappa have the 15823830 Jounce bumper.


            Front         (2) Frt        Rear        (2) Rear
            Stab Bar    Insulator    Stab Bar    Insulator
===================================================================================================
FE2 LE5            10342785    15887219    10342786    10350105
            27.2 x 4.5mm    27.2mm        24.2 x 3.0mm    24.2mm
===================================================================================================
FE3 LNF Non-Z0K        15224873    25789241    15224878    15224881
& LE5 Z0K             33.3 x 4.5mm    33.3mm        25.4 x 3.0mm    25.4mm
& SDT (street edition)
GM SPO Perf Parts                           
===================================================================================================
FE3 LNF Z0K        25855621    25789241    25855622    25855623
                   33.3 x 6mm  33.3mm      27.2 x 6mm  27.2mm
                                  Also needs
                                  25855624 clamps
===================================================================================================
I also added it as a txt file.

The shocks have a sticker on them with a code.  Springs usually have a tag that is a specific color and has the part number of the spring on it.

Also, keep in mind that the Z0K (both LE5 and LNF versions) are built with two spring seats.  Out of the factory, the trim height is within specification with both spring seats, which was necessary due to several areas in the assembly plant that prevented a lower car from getting through the system, as well as shipping limitations at the intended ride height.  It is up to the owner to remove this 2nd spring seat/spacer to set the car to intended carrying height.  This option was lower cost when compared to other options, such as lifts and/or disposable spring stuffers.

You will also notice that the same shock is used for the LNF Z0K as is used for the lower spring rate cars.  This shock is not fully optimized for these higher spring rates, and the GMPP shocks will be closer but oriented toward heavier rebound damping than is necessary for the increased spring rate, and significantly tighter bypass (bleed), which is typically more desirable for autocrossing vs. street usage or road racing.  It is assumed that anyone buying an LNF Z0K for T2 or serious AS autocross would be replacing stock shocks, no matter how they are tuned, with their own choice in Penskes, Olins, Konis or other racing or adjustable shocks.

I just found the answer to my own question. The NA's had different specs. The RL/GXP do not.

The shocks and springs are different.

[GXPinKC]

Thanks for the thread Kennysaberese.  If you look on page 118 of the Pontiac Solstice Book there is a chapter eight, "My, How Sky Flies", Gary Witzenburg goes into the differences between the roadsters.  Lots of pictures as well, pages 118-128.  He also covered parts of what you mentioned at the Nashville National Meet, as well as Steve Padilla who addressed some of the finer parts as well.  I would love to drive a Red Line myself as I would like to find out how it drives compared to my GXP.  Thanks again for the great thread.

[kennysabarese]

Ah cool, I don't have the book. I should get a copy.

The GXP and RL are the same suspension so they probably behave very similarly. The Sky probably has a little more weight due to more options.