Kevin,
Why would mine measure that far off? I haven't figured up exactly how much my measurement points would have to be off for my IC to come out where yours did..... but I would guess all my measurements were +/- 1/4" accuracy.
My measurments are as follows:
RLCA rear point = 8-7/16" off ground
RLCA front point = 9-3/8" off ground
RLCA = 20" long
RUCA rear point = 17-3/8"
RUCA front point = 17-1/8"
RUCA length = 11-1/8"
Autocad says intersecting point is 10'-8 15/16" ahead of rear axle centerline which falls about 22" in front of front axle centerline
This point was 14 7/16" off the ground. QUOTE]
I don't know why they are closer. You do need to be within 1/8" for accuracy tho b/c the control arms are so short an 1/8" of error can move the IC a looong ways.
If you look at your #'s and subtract the UCA and LCA chassis hole measurements then you get: 17.125"-9.375"=7.75"
Mine for my car are: 17.25"-9"=8.25" (both of my graphs are 8.25") which may not be that far off if your numbers are not accurate. Also, there could be that much slop in MFRing tolerances which is why I prefer to plot chassis out before making changes.
Our Axle measuremts are about right on, tho at approx. 9".
BTW, you do NOT use the actual control arm lengths, instead you use the perpindicular distance to the axle centerline of the arms.
ks