Making IRS work without going to mendeola truetrack... :)

[Humble]

There are 2 schools of thought on this:

Heavier springs, with lighter sways to fine tune
or
Lighter springs, with heavier sways but more reliance on shocks to tune

For autox and hill climbs where the corners come at you fast, you want to keep weight transfer minimal so the car can react faster. I've found the best way to do this is with heavier springs, so they do most of the work and then you can fine tune it with a sway bar.

Weaker springs won't be able to deal with high cornering loads slick tires can generate even with a ridiculously large sway bar. You'll end up lifting a wheel and losing 1/4 of your grip.

With both setups you have to tune your shocks accordingly or it's all for nought.