Jody,
You are quickly becoming my favorite on this site. Anyway I have already applied for membership to the almighty corner-carvers. I'm not rying to be a smart a**, but I know alot more about suspension geometry than super charging and I am intimidated just from reading the rules. I do admit from browsing the forum they know what they are talking about. I'll see how long it takes me to get blasted.
Mark,
Thanks alot for the info. I do have a suspension program and I have read the book several times. I even have it highlighted and tabbed. That's pathetic. Packaging may be an issue, but since I am building the chassis from scratch I have a bit of freedom. I felt the same way about his example.
One od the biggest down falls for me so far is the scrub radius. Since this is essentially a street machine we want some dish to the wheels and with a 10deg KPI its tough. I was thinking of running a 2" dropped heidts spindle to help with scrub radius. I can correct the bump with the placement of the rack.
I am only designing for 2 deg roll. But when I try to get the camber gain down to where you suggest the roll center migration right to left is terrible. I am still crunching, but it is challenging. To get this my upper arm is almost 50% of the lower and it is at about 5 deg. Is the .7/inch in the first 2 inches really adequate for the flat corners that street driving gives? I guess it is or you wouldn't have said it. With this set up when I am at 1 deg roll the roll center moves 7 inches. At 2 deg it is 15 inches. That to me is unacceptable. If I maintain the same arm lengths and change upper arm angle to 15 deg I get about 1.7 deg -camber gain per inch. But when I roll 1 deg the roll center only migrates 1.9 inches and at 2 deg. it's only 3.9". To me that is pretty good. With the latter setup the roll center is at 5.2" above ground and only moves .375" in dive and roll. This helps with the taller polar moment that you spoke of allowing me to run softer springs with less roll. With the first example the RC is 1.8" and moves down 1" in dive and roll. What do you think or am I missing something? The problem I do see with the aggresive camber gain is tractive effort under hard braking. I could have up to -6 deg under full dive.
I will have some anti-dive built into the front, especially running a big block with power adder.
Any comments based on the above are appreciated.
By the way, I am also considering the ATS AFX spindles, but I need to call and get some dimensions I can layout. Any thoughts on these for a clean sheet application?
Thanks,
Chad
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