C6 coilivers

[stevesteve111269]

Further to my previous message I've decided (I think) to go down the coilover route. Any feedback from c6 owners who have done this would be helpful. My car spends the majority of its life on the road ( as opposed to a track.... not a ditch lol) so ride height is important, bearing in mind this is the main reason for the change away from the leaf spring. BC racing br series looks good. Any thoughts? Thanks

 

[teamzr1]

Requires you thinking about the coilovers you choose, the spring rates front/rear and if the shock's mounts are correct with the mounting points of car so that the coilovers clear anything near them and shocks are at correct angle

selecting the wrong spring rates in front and back can end up with front to stiff or too soft and same for rears
You may need stronger rates on fronts due to engine and tranny weights and software in rear and causing too much under or oversteer so select your spring rates carefully

Then need to do a full 4-wheel alignment after you set coilover heights and as I show in testing this on my 1994 ZR-1
is corner weights and assuring center of gravity moved to center of car

Also as I show below the weight changes when ridding the transverse springs

Custom Suspension Project

Team ZR-1 Motorsports is a FREE Services Club related to Corvette, Racing, LT5, Chevy, Chat, and Free Membership

teamzr1.com

I used to have multi spring rates and would change them depending on street or track use.

 

[Dorsetsteve]

Mines on Yellow Speed Racing ones, fitted by a previous owner. From what I understand they are on 8kg front 10kg rear. The ride is pretty good to be fair, but I would say the body roll is more than you’d want, I suppose that’s because the leaf is part of that compensation in the stock design.

 

[teamzr1]

You have to measure what the corner weight at each wheel is as I showed on my website write-up where
I corner measured and then adjust the height of each coilover to make it equal on each wheel with center of gravity
moved to center of car.
I also showed using adjustable end links and the thickness of the sway bars to set the amount of body roll and under/oversteer

If we convert 1 kg/mm = 56 lb/in so 8k/mm = 448 ft/in
That means a coil spring with a spring rate of 448 lb/in will compress one inch for every 448 pounds of load applied.

With all the weight of the engine the front coilovers needs to be higher the 8k/mm as to smaller rate would allow more weight on the springs and can cause oversteer, more body roll in the front

10k/mm= 559 ft/in so using those up front would be stiffer and less oversteer/body roll

 

[Dorsetsteve]

I don’t know what the previous owner did or didn’t do in the set up respect. The type of split with lighter fronts seems to be typical of all the manufacturers of these coilovers. I can only say the car doesn’t do anything negative when pushed but I’ve only driven it on the road.

Over winter I want to pull the lot and replace the old/worn bushes I find and install the anti roll bars with the end links. At this point I will have it set up properly.

 

[Blackzed]

Do remember that when you set it up there is a factory rake front to back, I believe it is 3mm or 5mm. Without this it will get floaty at speed, found that out on corvetteforum.com when I was adjusting my Z06.