[thstone]

"max out the negative camber on the front, subtract one degree from front camber for the rear camber, and zero out the toe."

Yes, this is a great place to start and about as good of an alignment that you're going to get from a Boxster with staggered tire setup. Unfortunately, this will not get you anywhere near GT3 or RS handling.

The next step is to add adjustable lower front control arms (the 996 GT3 front lower control arms) and go to a "square" setup with another set of rear wheels and tires in the front. This will let you get at least -3 deg camber in the front which gives the front a ton more grip and eliminates understeer. When you go square, you will also want to install the front and rear adjustable sway bars. If you just install the wider tires in the front, you'll get a lot of oversteer in the rear. The adjustable sway bars allow you to fine tune the handling to mostly neutral. With a set of grippy summer performance tires, the car will handle more like the GT3/RS feel that you're looking for.

And you really don't want jaw wrenching stiffness if your goal is to go fast. You need balanced control that inspires confidence to push the car to its limit. Thus, most Spec Boxsters have the adjustable rear sway bar on the least stiff setting or even disconnected to allow the rear suspension to do its job keeping the rear tires firmly and squarely on the pavement. The front adj sway bar would be set at the middle setting to start and then adjust to your preference from there.

Best of luck.