[strat61caster]

I think the equal/softer rear main spring comes from a few ideas that some people seem to stick to real hard - zero toe, positive rake, bump stops that basically make the main spring useless, bound up or overly stiff swaybars, weird damping, ride heights. There’s too many variables to really nail down a “perfect” setup or say X/Y is the right combo, for better or worse I find this car to be really spring insensitive, especially if you’re dealing with a particular problem such as alignment issues or a compromise setup like a damper that’s inadequate or set wrong. For instance I’ve tried 325#/425#/500# in pretty much every combo, even 500F/325R, a degree of camber has had a bigger impact on balance then going +/-100# on the spring rate did.

Edit: also with a soft rear vs a stiff one I could see better driver confidence with a rear end that moves vs one that doesn’t move and you have to have a better feel for the tire slip angle as well as anticipate any track bumps/irregularities.