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Hi folks, I just recently joined the boards, after buying my first 'Vette two months ago. I mentioned on an intro thread that although I love the car already, it feels way to "floaty" in base trim, and I will add the Z51 suspension soon. Everyone was super welcoming (really appreciate that!), and although this topic has probably been beat to death, several others asked for my impressions on the suspension upgrade. I'll raise y'all one, and add some actual data!

Go ahead and make a sandwich first, this is going to take a minute...

A little context / background:
I purchased a base model on purpose, despite a very long history of performance vehicles to see if I could live with a 'Vette as a daily driver. I'm blessed to live on some winding, hilly roads that are well-maintained, and comprise about 2/3 of my daily commute. My last car was a 2016 Camaro 2SS, and over the last few years I noticed: 1) that car has done great things to make my commute more enjoyable/bearable and, 2) I almost NEVER have a 3rd passenger, anyway. So I decided to up-my-game even further, and swap into a 'Vette. It's turned out to be a great daily driver (in my case, anyway), and there's a lot to love, however, right away I noticed that the base C7 suspension ain't gettin' it done!

Okay, so back on-topic...

I was originally going to do the sway bars first, and the shocks second, taking measurements in between. However, after the RPITA that the sways ended up being, I elected to do it all at once. BTW–that's not the 'Vette's fault. Sway bars on the 'Vette are MUCH easier to access than nearly every other car I've owned. I just didn't originally have the crowsfoot adapters to torque the link nuts, with the car already apart and up in the air!

Here is my subjective assessment:
So first, the obvious–it's firmer. I mean... what did you expect–Haha! However, my impression is that it's 1/4 harsher, and 3/4 "tighter." It's not actually TOO harsh for anyone, but might be firmer than you want, especially if you're the type of driver who rarely flicks their car hard into a corner. You're going to feel a LOT more of the road, and although some people appreciate that, some find it annoying. In my case, I'm used to more rigidly-suspended vehicles, and the "roughness" of the Z51 suspension strikes me as perfectly average for a factory sport car with all the "go faster" boxes checked on the window sticker. For example, I think all the following cars are softer-riding: BMW 3-series, Mustang GT, Camaro SS, Dodges. I'd consider these about equivalent: BMW M3, Honda Civic Type-R, Nissan GT-R (not Nismo).

Now to the good: First, the steering feels MUCH better with the Z51 sway bars and shocks! On-center feel is greatly improved! The roll-translation is way lower... like 75% lower... and offers more precise feel and quicker response. Much less "wallowing" on left-to-right transitions! Secondly, the dynamic body movement is better controlled. Compression damping seems about 20%-40% firmer–although that's really only going to be useful at the track or triple-digit speeds. Rebound damping, on the other hand seems at least 50%–maybe up to 100% firmer, and it was badly, BADLY needed. The base model obviously relies on the C7's fantastic suspension geometry and low center of gravity to hook-up a corner, and although the base car can actually corner pretty hard at the limit in terms of lateral-g, it lacked a significant amount of body control–especially on rebound.

To sum up, I believe the Z51 suspension upgrade for base model cars feels only marginally rougher, but much more sure-footed and confidence-inspiring, and in turn it makes the cornering performance much more easily accessible, especially at the limits of grip.

Now the objective stuff:
I used a sensor app to gain access to the accelerometer/gyroscope on my iPhone, and used gaffer tape to mount it squarely to the center console for data acquisition. It's not the most precise way to go, but a heck of a lot better than the car's built-in G-meter. It was sensitive enough to pick up on me gently tapping the steering wheel with my left index finger, despite being way over on the center console–"that'll do Pig"! I crunched out some graphs using the quick-n-dirty method for matching up before and after data by tying them to the same section of the road (using longitude only, but it's a continuous north-south route). However, the original data is on hidden sheets, and if anyone wants to get froggy and throw some GIS methods at it, it will probably yield a more precise answer. The data is linked below in .xlsx format, and shows lateral acceleration, gyroscopic acceleration, and attitude rate (roll, pitch, yaw). It was recorded over 90-ish seconds at a 25hz data rate. The test route is generally north to south, with the beginning of the run happening at a about 30mph, increasing to 50mph, and going over a combination of left/right turns, and elevation changes. Generally the same outside temp, humidity, weather, speeds (within my ability to control it), and full operating pressures/temps. It's not strictly scientific, but hey–better than nothing.

https://www.dropbox.com/s/athmsgxkldskx7i/Z51_Suspension_Test_Run.xlsx?dl=0

for reference, the axis of the car for testing are:
  • X-axis, front to back
  • Y-axis, left to right
  • Z-axis, top to bottom (adjusted for gravity)
...gyro rotates about the indicated axis, and so does attitude. Attitude is the rate of rotation about an axis, and gyro is acceleration about an axis.

The data doesn't show anything earth-shattering, but it does confirm a few things:
  • Z51 sways/shocks impart a slightly higher peak load at low speeds but this reduces and actually becomes slightly better (lower peak load) as speed increases.
  • Likewise–any difference in mean shock load is negligible.
  • Total dynamic movement (area under the curve) isn't greater, the Z51 suspension just makes it happen faster and gets it over-with quicker, occasionally making higher peak forces in the process.
  • There is a small but surprising improvement on pitch and gyroY–probably all due to shocks–that might help limit braking, though I didn't watch for this specifically.

Although you can lay the graphs over each other, there's a lot of noise, so it might be easier to lock the vertical axis for a particular view and switch between with & without Z51 to see the differences.

-Cheers
 

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A great comparison, Grnflash! I've found the Z51 suspension quite liveable on a daily basis. I've owned mine since October '13 and do not have MRC. For over a year the Corvette was my daily driver, and even now I average about 900 miles a month hitting twisty roads near me - I'll hit 83K miles in another week or two! The only time I notice any harshness the tire pressure is over 35 psi and on rough pavement. As long as I keep the tires at 30psi cold, all is good!

Are there smoother cars out there? Absolutely! But none of those can equal the grin factor of a Corvette. I would think if a super-smooth ride is paramount to any reading this, consider the MRC. In tour, the roads are much smoother than a Z51 (possibly even a non-Z51), yet in track it will handle better (tho ride more harshly). The non-MRC seems to fall right in the middle, and I'm quite pleased with it.
 
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I’ve owned my 2015 Z51 7 speed manual for about a month. I drove it 600 miles home from the dealer in Florida in Sport and decided this was not a long trip car. I continued to drive it in full Sport for a couple hundred miles around town. Since then I have familiarized myself with the car and my preferred setup is Tour suspension, automatic steering (which I believe defaults as tour) and track sound. Love the softer Tour suspension on our local roads.
 

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A great comparison, Grnflash! I've found the Z51 suspension quite liveable on a daily basis. I've owned mine since October '13 and do not have MRC. For over a year the Corvette was my daily driver, and even now I average about 900 miles a month hitting twisty roads near me - I'll hit 83K miles in another week or two! The only time I notice any harshness the tire pressure is over 35 psi and on rough pavement. As long as I keep the tires at 30psi cold, all is good!

Are there smoother cars out there? Absolutely! But none of those can equal the grin factor of a Corvette. I would think if a super-smooth ride is paramount to any reading this, consider the MRC. In tour, the roads are much smoother than a Z51 (possibly even a non-Z51), yet in track it will handle better (tho ride more harshly). The non-MRC seems to fall right in the middle, and I'm quite pleased with it.
Absolutely. My wife’s fun car is a Lexus SC 430. 300HP 8 speed electronic transmission double wishbone suspension. Quick like a slot car, very soft luxurious ride but will hug a curvey road like it’s on rails. BUT IT’S NOT A CORVETTE! Love my 2025 Z51!
 

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2015 lol
 

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Thanks for the write up. I have a base C7 with Mag ride so I am not going to go full Z51 suspension but I am going to Z51 sway bars and combined with the Mag ride I think it will tighten down the cornering quite a bit. With the Mag ride's in sport mode it's nice and firm and I wouldn't want it any firmer than track mode thats for sure. I'm fine with my car not having the bigger brakes of the Z51 and the dry sump set up. The E-differential is probably the best part of the Z51 package.
 
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