327 Chevy Timing Chain Installation
Article by Mark Trotta
An old chain stretches from wear and will alter engine timing. If you're not sure how many miles are on your old Chevy V8, it's a good idea to replace your timing chain when replacing the cam.
The engine featured in this article is a 300 horsepower 327 in a 1966 Corvette. All Gen-One small-blocks will follow this same procedure.
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NOTE: On a first-gen small blocks 1965 through 1986, the timing chain is difficult to access with the engine still in the car. Not only do you have to remove the alternator, water pump, and other stuff, the front of the oil pan needs to be dropped about an inch.
Once the timing-chain cover is off, the three cam-gear bolts are removed. Cam gear and timing chain are come off together.
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SBC Timing Chain Kit
For this 327 engine, I selected a Cloyes True Roller 9-3100 kit. The double-roller chain features solid bushing rollers that really roll, and the pitch diameter is larger than stock, making it less prone to stretch.
The Cloyes cam sprocket is cast iron and dynamically balanced to 5,000 rpm. That equates to 10,000 rpm engine speed.
A double-roller timing chain with steel gears is really all you need for a street-driven car. Beyond that, it's all about style and attitude.
For More SBC Timing Chain Options Click Here
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SBC Timing Chain Install
Gen-One Small-blocks use a "dot over dot" method to align the upper cam gear to to the lower crank gear.
On the cam gear, note the manufacturer's pre-marked timing dot, which should be at the 6 o'clock position.
Rotate the crankshaft until the same dot on the crank gear is at 12 o'clock. This sets the engine's rotating assembly at Top Dead Center (TDC). The front drivers side piston will be all the way up in the bore.
Bolt the cam sprocket to the camshaft. Make sure the sprocket is pulled up flush onto the cam.
NOTE: There are three keyway slots in the Cloyes 9-3100 crank sprocket. This allows you to set the timing either 4° advanced, 4° retarded, or factory standard. For this installation, the factory setting was selected.
Double check that the timing marks are positioned properly. For good measure, snap a picture of it.
Wrap the timing chain around the cam gear, and then under the crank gear.
TIP: With a socket and ratchet on the crank bolt, I back up the rotating assembly slightly and then forward, lining the dots up again, to make sure I am getting the most accurate reading.
You can add a dab of non-hardening sealant on the three cam-bolt threads and torque them to the specified 30 lb/ft. This will insure the bolts remain torqued to the proper specification. A camshaft bolt locking plate can also be used.
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327 Timing Chain Cover
Before the timing chain cover was re-installed, it was sanded down to bare metal, treated with phosphorous acid, then painted Chevy Orange (no primer required).
A new Felpro TCS45121 timing chain cover gasket was installed.
Timing chain cover bolts require 7 to 9 lb/ft of torque, no more.
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Classic Car Engine Oil
The 10W-30 oil your car left the factory with is not the same 10W-30 that you buy today. There are more flat-tappet hydraulic cam failures than ever before, brought about by inferior foreign lifters as well as the removal of ZDDP additives from motor oils.
Read: Best Oil for Classic Cars
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Articles of Interest:
SBC Camshaft Selection Guide
Best Engine Assembly Lube
SBC Timing Chain, Gears, and Covers
Tools Needed For An Engine Build
327 Bottom End
