OFNA Racing OB4 RTR - Manual (Page 40)

ENGINE BREAK-IN AND TUNNING
(BREAK-IN THE ENGINE BEFORE DRIVING THE CAR!)
TUNING AFTER BREAK-IN
Idle adjuster screw.
Lean
Rich
• Choose a wide clear outdoor location with low dirt and dust.
• Set the car on box or holder with wheels off the ground.
• Turn on radio and car. Make sure throttle is at idle position.
• Fill fuel tank and set master engine needle.
• Prime fuel line and Heat glow plug before pull starting engine.
• When started, let engine fast idle for two tanks of fuel.
Close master needle by turning clockwise until it stops.
Then open needle by turning counterclockwise 3 turns
(rich setting).
When running car, adjust carb with 1/8 clockwise turns,
slowly leaner, until the top speed good. Check engine
temp, if possible, for no more 250 degrees.
Adjust barrel stop so it will not close, accept for a small gap.
This gap will be the idle setting. You will notice the idle will
increase with a wide gap.
Adjust low end needle for best throttle response. Use only
small turns. From idle, give it full throttle, if throttle is slow
lean out needle until good.
REMARKS:
CIRCUIT/
DATE/ MOTOR: TIRE(F)
C/F TEMP/
SETUP SHEET
WET:
TIRE(R)
T T
T T
T T
T T
1 2 1 2
GEAR RATIO
Front Center
BEST LAP
' "
1 2 3 4 5 6 7 8
Lap 1
Lap 2
Lap3
Lap 4
Lap 5
Lap 6
Lap 7
Lap 8
Lap9
Lap10
Lap11
Spur Gear Clutch Gear
Hardness of
Differential
Rear
FUEL: