SS Sedan Springs under the 2011 Caprice PPV

[Pursuit]

Ok, the 2012+ front struts and the SS springs are installed. The short story here, with the pics and measurements to follow.

Parts used: Front SS springs GM 92290030
Rear SS springs GM 922290028
Front Struts RF GM 92263478
LF GM 92263479

The car sits 3/4" lower at all four corners. The suspension is still definitely on the stiff/sporty side but the "pickup truck bounce" in the rear is much less. I have a stretch of road that the concrete panels in the road have all tilted, that will create a rhythmic pogo effect on the rear of the car. It is much less now on that stretch of road.

[Pursuit]

The left side measurements before and after. Measurements were made per Bill Harper's recommendations. From the top of the wheel arch, through the center line of the wheel center to the bottom edge of the factory steel rim. The car has a full tank of gas, two batteries and full size spare.

[Pursuit]

And the right side

[Pursuit]

Top view of the front and rear springs SS and PPV. You can count the amount of coils per spring. I do have the coil count, free height and wire diameters, but I do not have that info with me. I am on the road with work. I will update this weekend.

[Pursuit]

And the markings on the right front strut.

[orgdnr]

Looks as if the SS coils are 3/4 turn less. I wonder if the coil diameter and wrap are the same. If you were to imagine the ppv coil cut 3/4 of a turn, do they look the same?

[Navy Lifer]

I think it indicates we're on the right track with springs that lower the car, but are not called "lowering" springs, which all too often create other issues. This fits in with the 94-96 Impala SS springs installed on a B-body Caprice--it was a factory fitment, didn't harm ride, and gave the car a little more aggressive stance--it wasn't the ticket for actual LE work, but it was a very good compromise for Caprice (including 9C1) owners who wanted to close up the wheel to opening gaps and still preserve good ride quality.

The production springs for both cars (9C1 B and PPV) were created with the thought that the base vehicle load equipped to in-service specs was going to add a good bit of weight, so the many PPV owners here not using the car in L.E. mode can see what a spring change will do to the car both visually and in resulting ride characteristics.

Imagine using some of the various lowering springs offered for G8 or SS on a daily-driver (non-L.E.) PPV--the drop would be significantly greater, and I just don't see how that would look "right", based on PPV tire sizing (which can be easily changed). The other question with lowering springs is how close to the limiters/stops the suspension ends up with aftermarket springs--ie. how is ride quality impacted by greatly reduced suspension travel (before hitting bump stops)?

I like the results--helps me with my concerns as to how it would work out when I began considering this option in the first place.

Thoughts and curiosity on a few things:

1. remember that tire diameter on PPV is larger than SS or G8 - put OE wheels and tires from G8 or SS on the PPV, and it would again look as if it could be lowered further

2. Maurice, is there any way you can relate the change of both spring and front strut as far as the impact on road behavior due to the updated valving in front? I wonder how much of what you describe on that section of planked road is the struts vs springs....

3. Curious what the dealer's reaction/thoughts were on you doing this--before & after.

[elc32955]

Bill, just a quickie for you - remember I am running stock/OEM G8 GT wheels with RSA's on my 2011. If you look at the masthead pic on the opening page you get a good indication of how the car sits with those wheels on the PPV springs/struts.

Eric

[Navy Lifer]

Understood, Eric.....my comment specifically included "tires", in the case of G8 or SS--just as Camaro OE tires are taller than even PPV, it's my concern that no one misunderstand that tire diameter, especially, will affect the visual impact of lowering the vehicle.

That gets into the whole "how much sidewall do you prefer" conversation. G8, SS and even Camaro don't use a 50 aspect ratio tire at present, as does PPV. This gets into the realm of relative ride comfort, handling/response, tire load rating, wheel sizing (whether for looks, for brake clearance, etc) - the greater weight of larger wheels is another consideration in all areas--ride, acceleration/braking (inertia), cost of tires, rim damage protection....the list goes on.

Then there is calibration--impact of tire diameter on final gear ratio, speedometer accuracy, etc. Generally it's small, but it still matters, especially if a PPV owner wants to know that the "certified" speedo is indeed correct.

[Pursuit]

Bill,
I have only driven the car 20 miles but I did focus on the known bad roads that I mentioned. My first impression is that the struts aren't as sensitive or over reactive . It seems as though the steering wheel is "calmer". This is just an observation while the car is driving in a straight line on the interstate. I am by no means a technical driver but I can discern subtle differences.

My Caprice is the only one the dealership has seen. It always draws a few onlookers. The technician at the dealership did express a concern as to who would be to blame if the swap didn't work out. The service writer (who is my next door neighbor) said it would be on me. He does know that I am constantly researching, modifying everything I own. The suspension swap and four wheel alignment was an all day affair. But, the dealership offered a courtesy Silverado to drive until it was done

This is the first time that I have had a dealership do any work for me other than the Certified Pre-Owned afforded oil changes and tire rotation. My goal is to develop a relationship with the dealership with both parties knowing that I am not a "normal" customer. I know the service writer, the parts guys and the father/son owners.