Grabbed_Crow_Mobe

The scales themselves are accurate within a pound. I think the question is how far from perfect do the weights need to be before you have detrimental effects on handling. I've read various opinions on this but apparently 3% is where it starts getting ugly. No idea how true that is. Personally, I didn't feel or notice the car behaving differently once I started dialing in my weights but my lap times have come down.

fatbillybob

scale accuracy is not an issue but suspension stichion is! That by far is the biggest issue we face with vettes in attempting to scale for accurate results.

davidfarmer

I can get coilovers within a few pounds....leafs I usually get within 20 or so. If you make additional adjustments, you almost always overshoot because of "stiction" as fatbillybob says.

Nowanker

OK, finally had a car to scale.
Already know that having the hood and/or deck lid open makes a difference, and that trying to balance a car with the swaybars connected will keep you amused for the entire day.
Was very skeptical of (reasonable) tire pressure making any difference at all.
Tried it at 40psi, X weight 50.1%
Lowered pressures (all 4) to 32psi, 49.6%
...learn something new every day!
Thanks, NoKones!

romandian

so i have been thinking, why not balance the car by adjusting the sway bars? would be simple.

Nokones

Nowanker:
I am glad I was of some help.
Romandian:
That wouldn't be a good idea. The sway bars are supposed to be free from any pre-load when the car is standing static.

davidfarmer

you don't want your springs and sway bars fighting each other, that would give you different spring rates at each corner as they would help each other in some instances, and fight each other in others.

Springs support the car, shocks control the springs, and bars control roll. Let them do their jobs.

romandian

not sure i get it. when you jack up the car at one corner there is more weight, which precompresses the spring thus increassing effective spring force. the bar is just another sprig doing the same, no?

Nowanker

I don't know the specific answer to that.
I suppose it would work....
Also see that approach as an opportunity to work your set up way, way out of wack.
I'll stick with the step by step approach:
Alignment is not wacky/tire pressures at hot track PSI/mid race fuel load/ballast to driver weight
Disconnect swaybars
Set ride height
Minimal fine adjustment to bring balance where you want.
Reconnect sways, ideally with adjustable links to avoid screwing up all your earlier work.

fatbillybob

Yes another spring but no don't use it that way because it talks to the other side. Springs control the chassis while bars control roll through the bars torsion spring effect on the other side. You do not use them to scale your car. You only want the bar effect in roll. That's why they make adjustable endlinks so we can passively attach the bars at the scaled rideheight.