Charley Hoyt

I need some advice about suspension. I have a C6 Z51 convertible that has Z06 fenders, wheels, and sway bars. I would say that I am an intermediate track driver (which means that I know enough to know that there is sooo much more to know). My question is about the springs on my car. Is it a good use of a few hundred dollars to switch to the C6 Z06 springs to match the wheels and sway bars? Right now my car handles very well and feels well balanced. Although I suspect that I spend a lot of time on the bump stops while cornering. I am not sure if ,or how much, the stiffer springs would improve the handling? Any advice would be appreciated. Here are a couple of pictures of the cornering.

Thanks for the help.

Charley

davidfarmer

I haven't compare rates, but I do find that a Z51 C6 feels pretty soft when comparing back-to-back at the track. Some of that is the bars, some of it is the springs. If you have access to a pair at a good price, I'd say it's a no-brainer. If you are paying retail....I'd probably look into other options (VBP leafs, coil-overs, etc).

gkmccready

I don't think it'll help you much. The C6 Z51 front spring is the same as the C5 Z06 front spring and is 526#. The C6 Z06 front spring is 531# a whopping 6#/in increase -- I have never figured out why they even bothered with a different part. The C6 T1 front spring is 582#.

The rear spring, though, is 645# for the Z51, and 782# for the C6 Z06. The C6 T1 rear is 850#. Hyperco HPS are 565#/765# and HPT are 625#/850#.

VBP can manufacture springs up to around 1300# front, and I'm not sure of the max for the rear because folks seem to settle in the 700-850# range back there.

You might try Randy@DRM's trick of putting a ziptie on your shock shaft and see if you really are bottoming the shock. And I suspect most folks will suggest you try T1 swaybars before you mess with the springs.

What shocks are you using?

Charley Hoyt

They are stock Z51.

gkmccready

I'd consider a shock upgrade... you've got a lot more weight in your wheels+tires than those shocks were meant to control. They won't help where you ultimately end up in the corners, but they should control your trip to that amount of travel a bit better. But I'd also be tempted not to listen to me and ask LG, or DRM, or RAFTRACER, or ... :-)

Charley Hoyt

Thanks for all of the input....any other comments?

96CollectorSport

I find it funny that the official #'s from GM are within 6 lbs! We sell a lot of VB&P fiberglass springs for C2-3's and when you order say a 330 lb spring they will range from 320lbs to over 340lbs of actual rate. VB&P will have the actual number on the side of the box, you order 330 but they test each spring and that rate is written on the box to show the actual tested rate. So there is about a 3% range from high to low.
Let's say that GM has a tighter tolerance maybe 1% that would still mean that the differance between the C6Z springs and the Z51 springs would be within the tolerance.
So if you are going to change springs make sure it's worth while, there are plenty of vendors with a ton of experiance here to help you find what will work best for your particular set-up. Remember what works for street tires doesn't work the best for R-compounds, so make sure you tune your suspension for the tires.

gkmccready

The numbers I quoted came from VBP measuring the various springs, not from GM directly.