1970 454 Flywheel issue
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Joined: Feb 2006
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1970 454 Flywheel issue
I am having a vibration issue and wondering if the flywheel could be the issue ? Can someone tell me the correct size for a 70 454. The vibration is in neutral and at high rpm as well !
Team Owner
Joined: Jul 2004
Posts: 40,412
Likes: 792
From: Redondo Beach, California
Anyhow, the 454 engine is not internally balanced. The crankshaft damper and 454 flywheel have cast-in weights to achieve balance. The 427 engines are internally balanced and have neutral balance dampers and flywheels; i.e. no balance weights.
If the rotating mass of your engine is out of balance, something must have changed since it left the factory. Damper, flywheel, clutch assembly been changed?
..................................
The 427's had 3.76" strokes and are internally balanced. The 454's have 4.00 " which makes them internally unbalanced. If you buy a new 454 crankshaft today, a quality crank may come internally balanced.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
The actual flywheel has a diameter of 13 1/4 inches. This diameter does not include the starter motor ring gear. The clutch disk is 11 inches in diameter. The flywheel weighs about 25 pounds. The part number of my flywheel is 3983538.....I'm not sure I have an original 1970 Corvette flywheel. A part number for the 1970 high performance 454 is 3993827.
Anyhow, the 454 engine is not internally balanced. The crankshaft damper and 454 flywheel have cast-in weights to achieve balance. The 427 engines are internally balanced and have neutral balance dampers and flywheels; i.e. no balance weights.
If the rotating mass of your engine is out of balance, something must have changed since it left the factory. Damper, flywheel, clutch assembly been changed?
..................................
The 427's had 3.76" strokes and are internally balanced. The 454's have 4.00 " which makes them internally unbalanced. If you buy a new 454 crankshaft today, a quality crank may come internally balanced.
Anyhow, the 454 engine is not internally balanced. The crankshaft damper and 454 flywheel have cast-in weights to achieve balance. The 427 engines are internally balanced and have neutral balance dampers and flywheels; i.e. no balance weights.
If the rotating mass of your engine is out of balance, something must have changed since it left the factory. Damper, flywheel, clutch assembly been changed?
..................................
The 427's had 3.76" strokes and are internally balanced. The 454's have 4.00 " which makes them internally unbalanced. If you buy a new 454 crankshaft today, a quality crank may come internally balanced.
The damper will have an extra weight attached or a large "bite" out of the outer ring.
Jebby
