Stiff Front Sway Bar Thoughts

MaysEffect

Agreed, but if you use a stiffer sway bar alone you are increasing the load on the outer tire. This is no better of a solution then allowing a higher level of camber gain, certainly if you already have a small amount of static camber (-1.5 degrees or less).

The tire sidewall is going to start to roll over more with the increased load and then you still end up sliding more. Most sway bars on the market increase the roll stiffness by over 20%, in some cases as much as 100%. This is most likely greater than going up a spring rate compared to the oem springs. At this point its really up to the driver how they manage tire heat. with increased roll stiffness you will be heating the outer tire significantly more.

cloudofevil

But not necessarily in proportion. Which is way adding a stiffer sway bar to the front of certain vehicles like the Z and M3 is a good solution to reduce understeer.

MaysEffect

Ok, but how much stiffer? 25% stiffer? 75%?

It's directly proportional to how stiff the bar is compared to the spring rate and corner weight. Its all guess work unless the manufacturer of the asb states exactly how much force it takes to bend the bar, which absolutely no one does. At max, some companies may give you a percentage compared to oem. If you get a bar that has a greater resistance to bending than the spring rate, you may end up exerting too much force on the tires. This again goes back to the level of grip the tires can make. You may reduce the sensation of roll, but this doesn't garranty more grip. Where it may give an increased level of force to overcome traction loss, you run the risk of overloading the tire at the limit and having a sudden loss of traction when the tire lets go, compared to a gradual loss of traction. I personally wouldn't do this change alone unless i have a tire that can support a higher load rating. Presumably double that of the corner weight.

But i think we all can agree, the first modification to ever be done is tires. Only then should you decide to change the ASB and/or spring rate.

cloudofevil

Sorry I meant the benefit of staying lower in the camber curve and the detriment of increasing the outside tire load are not necessarily in proportion. I think in the case of the Z it's better to increase the front roll rate even with the increase in lateral load transfer across the front axle. And yes, tires are the most important upgrade.