327 Chevy Engine Timing Setting Instructionsby Robert Bayly
The 327-cubic inch Chevrolet engine is the third version of the Chevrolet small block engine that first entered service in 1955 as a 265-cubic inch engine with a 3-inch bore and 3.75-inch stroke. The 283-cubic inch engine came out in 1957 with a 3-inch bore and 3.875-inch stroke. The 327 arrived in 1962 with a 3.25-inch bore and 4-inch stroke. The 327 Chevrolet engine was available in many configurations, including a fuel-injected 375-horsepower model in the Corvette.
Set the parking brake. Start the engine and warm it up for a few minutes then turn it off.
Locate the timing marker on the driver's side of the timing cover at the front of the engine under the water pump. It sits directly over the harmonic balancer, the large round disc that the lower belt pulley attaches to. You should see numbers stamped on it: "BEFORE 12-10-8-4-0-4-8 AFTER." If you cannot see the numbers, spray the marker with carburetor cleaner and wipe it with a rag. Paint the numbers with some correction fluid to make them easier to see.
Identify the timing groove in the harmonic balancer. The timing marker, which is attached to the timing chain cover, sits about 1/4 of an inch above it. If you cannot see the groove, bump the starter over with the ignition. Do not start the engine. When you can see the groove, paint it with correction fluid. This will help you see the groove and the marks when the timing light flashes on them.
Remove the vacuum hose from the distributor and plug it with a small screw.
Connect the tach/dwell meter by clipping the red wire on the meter to the positive "+" terminal on the ignition coil. Clip the black wire to a clean metal surface on the engine.
Attach the timing light by opening the spring-loaded clip on the spark plug wire lead over the number one spark plug wire. The number one spark plug is the first one on the driver's side of the engine. Clip the red lead to the positive "+" terminal of the battery then clip the black lead to the negative "-" terminal of the battery.
Loosen the distributor hold-down clamp with a wrench.
Start the engine. Place the transmission in neutral. Check the tach meter. It should read between 500 and 600 RPM. If not, adjust the idle screw on the carburetor. Shine the timing light on the timing marker. The timing light will make the groove in the harmonic balancer appear to be stationary under the timing marker. Turn the distributor until the groove is at "4 Before." Tighten down the distributor clamp and recheck the timing. Reattach the vacuum hose to the distributor.
- The timing setting given is the most common for the 327. If, during a test drive, the engine seems a little sluggish, you can move the timing up two degrees to "6 BEFORE." If the engine clatters when you accelerate, move the timing down towards the "0" by two degrees.
- Use caution around moving engine parts. The engine will be running, and you will be close to the fan blade and fan belts.
Items you will need
- Correction fluid (Wite-Out)
- Carburetor cleaner
- Shop rags
- Inductive timing light
- Tach/dwell meter
- Wrench set
- 1968 camaro z28 hood air intake image by Jorge Moro from Fotolia.com