- BMI Racing DB12R - DArnold - Chesterfield - UK Nationals - 14.09.2008 -

 

Red = changes

Front End

0.020" BMI Front Springs with one coil cut off to make it work with standard rims. Found that standard length required too much pre-load and the springs were too stiff, killing some steering.
4 degrees of caster, if I need more turn-in I go down to 2 degrees
1.5 degrees of negative camber
CRC Front with Long Ball top arm for reduced camber gain to make the car turn-in more
Servo Flat, Corrally Center Point Steering to take all of the Ackerman out for way more steering
Fronts at 1.60" (this equates to about 1.66" for a big rim tire like the Prism)

Rear End

.064"-.066" Flex Plates (currently .064")
Angled flex plates .040" for more on-power steering than stock but down from previous .060" for a little more turn-in.
5K in Damper Tubes for faster chicane speed and a little more rear bite
35-40 wght Oil in the shock. Blue Spring for more turn-in, Red for more on-power
Rear Roll Center Raised .035" (shims at all points)
Batteries all the way back, smooths car, adds steering
Ball Stud Raised 2mm on Antenna Mount for more on-power
Rears at 1.70" (about a 1.76" for a big rim tire like the Prism)

Miscellaneous:

Only need to sauce half front and all rear now instead of all front and rear for prior setup and still have more steering! Car works the same using both Jack the Gripper (used two weeks ago) and Paragon.

I let the rears sit for 20min and the fronts for 10-15min, as the bite comes up I decrease the time accordingly. May try using 20K Diff Lube on front kingpins for bumpy tracks like the one I practiced at 2 weeks ago (I wish I had thought of it then even though the car was good).

Be careful about not over tightening the center pivot screws as this will cause a tweak, I found this out 2 weeks ago. Also, it seems that a tweak can occur if slop develops in the side pivots. You can check this by putting a finger under the flex plate and slowly moving the rear down. If you see the capture move off of the rear pod plate then you have slop. I had to take the top of the capture on the left side off and place a thin piece of plastic on top of the ball and that took care of it.

Other Equipment:

T.M. Tires (Pink/Pink normal, Magenta/Magenta or Gray Front/Tan Rear for high bite)
Tekin RS Pro
4.5 Motors
SpeedZone Batteries
JR Z3660 digital servo
KO Helios in fastest mode, no expo. 120% steering, D/R =92 of 100, Individual End Points = 85L/90R

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