Cooperative Fuel Research (CFR) Engine

==Preliminary Checklist==
# Check Engine Oil Level
# Check Coolant Level
# Open Coolant Valve for Pressure Transducer
# Input Desired Fuel
# Check Compression Ratio
## Micrometer Reading
## CR=(4.5/(Reading+0.5))+1
# Double Check The Head Is Securely Tightened
# Check The Valve Clearances
## Exhaust: 0.010”
## Intake: 0.008”
# Set Timing For Current Compression Ratio
## Compression Ratio
## Spark Advance BTDC
# Connect Ignition Wires to 12V Battery
# Turn On Circuit Breaker to Engine
# Turn On Lab Exhaust Fan
==Operational Checklist==
# Open Exhaust Gate Valve
# Engage Starting Motor
# Turn On Ignition Switch
# Turn Throttle to Wide Open Position
# Back Out Fuel Needle Valve, Adjust Until Backfiring Stops
# Let Engine Warm Up, Readjust Fuel Needle Valve as Needed
==Octane Testing==
===Conditions===
Engine Speed 	Constant at 900 rpm
Oil Pressure 	25-30 psi
Oil Temperature 	120-150°F
Coolant Temperature	209-215°F
Intake Air Humidity	25-50 grains/lb
Mixture Temperature	300°F
Carburetor Venturi 	19/32 in.
Lubricating Oil 	SAE 30
===Test Run Preparation===
# Turn on the main switches, crankcase heater, and coolant heater.
# Turn on the circulating cooling water. When coolant temperature approaches 180°F, turn the heater to low.
# Fill one of the carburetor bowls with regular gasoline.
# Start the electric motor, then turn on the ignition switch.
# Turn selector dial to the bowl containing regular gasoline.
# After the engine has run for a while, check the manifold temperature. Turn on the heater if it is well below 300°F.
# Check the specific humidity while engine is warming up.
===Bouncing Pin Adjustment===
# Check and record barometric pressure.
# Adjust the compression ratio of the engine to the corresponding micrometer setting (Manual page 96)
# Switch from regular gasoline to a reference fuel with a known octane rating.
# Adjust the bouncing pin to read 55+3 on the knockmeter.
# Adjust the elevation of the reference fuel bowl until a maximum knock is reached. This varies the AFR.
# Now, just read the bouncing pin to the 55+3 reading.
Note: From this point forward, do not touch the bouncing pin
===Testing the Unknown Fuel===
# Drain the reference fuel.
# Set up the four bowls in such an order that they can be easily remembered.
# Turn selector to the bowl containing the unknown fuel.
# Adjust the compression ratio so that the knockmeter reads 55+3.
## From this point forward do not change the compression ratio.
# Using pipettes and graduates, mix a reference fuel of iso-octane and normal heptane. 200 mL should be enough to run the engine and obtain a good reading.
## Use of conversion tables makes it possible to obtain known blends using the reference fuel with either the iso-octane or normal heptane.
# Turn the selector to the newly mixed reference fuel blend.
# Adjust the bowl containing the newly mixed blend to give maximum knock.
# Repeat this procedure until two reference blends not differing more than two octane numbers bracket the fuel.
# Interpolate between the two octane numbers to obtain the octane rating of the unknown fuel.
Note: If you want to test more than one unknown fuel, repeat only the 'Testing the Unknown Fuel' section.