More info on the set-up:
1.04 Mopar Performance TB's up front (~225 lb wheel rate)
1 5/16 x.250 wall Hellwig custom front bar (~475 lb wheel rate - 73+ k member)
MP 0" oval leaf springs (listed as 130 lb, though someone measured at 180 lb - these are not wheel rates. Also required 1.5" drop spacer)
Hellwig solid 3/4 rear bar (notes say wheel rates of 71, 82, or 96 - don't remember if this is wheel rate or bar rate - would need to run the numbers again to verify - currently on softest setting)
wheels are 18x9.5, +45mm offset. Tire allows a 9-10.5 rim width, and tire measurements on tire rack uses a 9.5" rim. Section with 10.7, tread width 10.2.
weight bias = 54.8% front, 45.2% rear. 3620 w/o driver. Bias didn't change on scales when driver got in.
Mopar handling line (used as a guide, not the gospel):
55% front bias = 77% front roll couple
54.5% front bias = 78% front roll couple
54% front bias = 79% front roll couple
53.5% front bias = 80% front roll couple
My math says I'm currently at 80% roll couple (using 180 lb for leaf), and can get 79% and 78% with rear sway adjustments. My 'goal' when picking components was to have some adjustment in the range that the handling line says I need, given it's theory and not a hard rule.
Currently I've got a bit of understeer. Max registered on the skidpad was .98 (peak, not constant). On the track, I was able to run down a number of great handling cars in the corners, albeit this occurred in the 'green' run group.
I'll play around with the rear bar soon, just wanted to fix the front tire wear issue first. I've also made it a point to only change one thing at a time, so I know what does what.
Car is a little lazy getting into the corners. Takes a split second to 'set'. Course, my only point of reference is shifter karts, which require a hard set with the steering wheel, which my instructor was trying to break that habit of mine in the duster.
Quote:
I'm sure you would..there is a reason I get paid a lot of money to help people set up their cars for the track. And my cars are always on the podium
And deservedly so! I'd sure appreciate you pointing me in the right direction, though!
The camber resulting from caster was something I was looking at this weekend. How significant is this when tuning a road course car vs an autocross car?
