[JLMounce]

I should clarify that we are talking about wheel rate, not actual rate. It would be the effective increase in resistance to weight transfer at the wheel.

A solid bar is more rigid than a hollow bar. A smaller diameter bar is less rigid than a larger diameter bar.

There are many different ways to skin the suspension cat on these cars. I am of the opinion that they are undersprung and under damped by a lot. My preference is to go with a stiffer spring and use a lighter bar to tune balance.

Others prefer a slinkier spring with a stiffer bar.

Since it sounds like you are going with the ridetech progressive rate springs, I would get their input. They’ll of course try and sell you on their muscle bar, but take the info and make a decision. Based on available data.

FWIW I’m not a fan of progressive rate springs. The idea on paper about having a soft spring that gets stiffer makes sense. Practical application I don’t believe in them. I’d rather have a linear rate spring and a good shock to control it.