Shoot, I posted a detailed response last night (took me about 20 minutes) and it seemed to post just fine. But, this morning, the whole entry is gone. WTF?
So, I'll have to be brief this morning, and not supply much explanation. Before I do, I'd also say that you will get hugely different opinions on some of these issues, depending on who you ask. It gets a little like discussions of politics and religion. Based on my own self-study of expert opinions (I'm not a suspension expert) here's my 2¢ worth.
Anti-squat:51% is too high for a light road car. A value between 10%-20% is better with 20% going to heavier vehicles like big
sedans.
Roll Axis Angle:This calculator shows the rear roll axis angle in isolation. It is an important indicator of the rear suspension architecture, but of more value when you have the front roll center too. Then, the roll axis will be taken to be the imaginary line connecting the rear and front roll centers, either static or dynamic. That will be a better indicator of overall vehicle performance. Having the F/R roll axis angle and the roll axis of the rear alone the same (or very close) is considered ideal by some designers.
Roll Steer:Neutral (as indicated in your output) is OK. Slight roll understeer is considered to be better for high performance driver control. Roll oversteer can be dangerous in a high powered vehicle - the rear end lets go easily in turns. Your V8 Locost is in that category.
Virtual Swing Arm Length:In your graph, that's the length from the "instant center" point shown in your graph and the center of the rear axle shaft on your live axle. If it's too short, you can have bad behavior like wheel hop under acceleration or axle tramp under hard braking. It can also be too long. Without going back and re-reading some reference books, I can't remember what the "ideal" is for a live rear axle, but (I'm living dangerously here) yours may be at, or approaching, that now. You'll have to research that particular issue. If you don't have access to some good references, let me know and I'll try and make some time to find it myself.
Adding in Front Suspension:All these values mean more (or less) when you have both a front and rear suspension design to look at. If you don't have a front design now, you might want to consider putting in the published dimensions for the Champion (Book) chassis front suspension. It will help you learn more about the front and rear as a system. That's what really matters most. If you have an "ideal" rear (or front) while the other end misbehaves, you'll not have a good design in the end, as one will spoil even the best attributes of the other.
If you're using a modified Book chassis, you'll have to alter the published Book suspension dimensions values to match the wider, higher or longer numbers for your chassis dimensions, as appropriate.
People spend
years studying suspension behavior. It's complex, so don't feel you're an exception if it takes some time to get your head around it all. In the end, it's all compromise, and non-geometric factors like tires, springs and shocks do play a big roll too. If you don't get it "perfect" in the geometry, you can use those latter variables to tune your suspension once on the road.
I hope this helps, and hope that the darn thing stays posted this time.
Cheers,