Negative Rollcenter Height

[wellis77]

As I wade through the mysterious world of suspension design I'm curious about the effects of negative rollcenter height (meaning below ground) in dive. I've got a lot to learn but one thing I've read regarding rollcenter height is that static height is good around 1-3 inches. One scenario I'm playing with has a roll center just above 1" but under 2" of dive, it goes negative. What are the effects of such a change?

Also, I have a theoretical understanding of anti-dive but is there a target that suspension designers typically shoot for on a car built for handling? I read that many race cars have 0% while passenger vehicles have as much as 30%+, is there a general happy medium for a performance oriented car?

Thanks for all the feedback. I'm learning a lot going through this and am enjoying the process but there sure is a lot of theory involved.

Will