dallara F303 - Page 5

5 TIRE INFORMATION
Tire dimensions depend on inflating pressure, rim width and camber angle.
These stiffness values are based on the recommended inflating pressure (hot tyres).
FRONT TIRE Avon Bridgestone Kumho Hankook Yokohama
Specification 180/55-13 180/55-13 180/55-13 180/550-13 190/50-13
Free radius (mm) 277.5 277.2 275.0 275.5 278.0
Vertical stiffness (Kg/mm) 17.0 14.4 18.3 (1.2bar) 17.5 17.0
Hot tire pressure (bar) 1.50 1.50 1.50 1.60 1.60
REAR TIRE
Specification 250/57-13 240/57-13 240/57-13 240/570-13 240/45-13
Free radius (mm) 287.0 286.5 288.0 286.0 288.0
Vertical stiffness (Kg/mm) 17.5 16.7 19.6 (1.2bar) 19.0 17.8
Hot tire pressure (bar) 1.65 1.50 1.45 1.60 1.60
loaded radius depends on tyre make, tyre pressure and camber
SUGGESTED SETUP
These set-ups consider the complete car with the driver seated in it, ready to race.
FRONT Avon Bridgestone Kumho Yokohama
Ride hei
g
ht
(
mm
)
15 16 16 15
Camber
(
de
g)
2°45’ 3°30’ 3°45’ 3°45’
Toe
(
de
g)
(
total two wheels
)
20’ OUT 10’ OUT 20’ OUT 20’ OUT
S
p
rin
g
s
(
lb/in
)
800 700 700 800
Vertical Pre-load
(
mm
)
8668
Dam
p
er static len
g
th
(
mm
)
335 335 335 335
Solid s
p
acer
(
mm
)
6666
Push rod len
g
th
(
mm
)
Roll centre settin
g
STD LOWE
R
STD STD
Roll bar settin
g
<<<>>><<< <<>><<>> <<>><<>> <<>><<>>
Roll
p
re-load
(
notches
)
none none none none
REAR
Ride hei
g
ht
(
mm
)
27 28 26 28
Camber
(
de
g)
1°45’ 2°30’ 3°00 3°15’
Toe
(
de
g)
(
total two wheels
)
10’ IN 20’ IN 20’ IN 20’IN
S
p
rin
g
s
(
lb/in
)
900 800 800 800
Pre-load
(
mm
)
none none none none
Dam
p
er static len
g
th
(
mm
)
335 335 335 335
Push rod len
g
th
(
mm
)
Roll centre settin
g
STD STD STD STD
Roll ba
r
21 OD 26 OD 21OD 21OD
Differential settin
g
60/80#4 60/60#6 60/70#4 70/80#4
A well balanced car will make the driver come closer to the car’s limit.
• In fast corners aerodynamics (ride heights and wing settings) have more influence on the
balance than in slower corners.
• In mid-and slow speed corners the weight distribution and the differential settings are most
important.
• Tune the dampers to the chosen springs, not the springs to the dampers.
• Always pay attention to reach the correct tyre temperatures. No car can reach its limit on too
cold tyres. No car can be reasonably balanced with a significant difference between front and
rear tyre temperatures.
• Run the car always as low as possible, although without going stiffer on springs for running
lower.