Engine Balance?

[Jeff65]

If you buy a '68-'81 302 then it will be 28 oz-in imbalance engine requiring matching components (flywheel or flexplate and harmonic).

If you buy a '87 or later 302 chances are it will be 50 oz-in imbalance engine requiring matching components.

If you buy another Ford small block engine between '82 and '87 you'll need to know whether its a 5.0L or 302 engine. In this case I would get specific information from my Ford dealers parts counter about the specific production code stamped on the block.

The seller is telling you the engine is internally balanced to rebuild specifications. Full engine balance is not done as a routine matter. Balance is close enough for passenger car service without further fuss. Thus, you use the proper matching components and thats all you gotta do.

Now if you're fussy and want a racing engine, then you wnat what you think you want...that is, a fully micro-balanced engine. To get this, you want a engine built by a racing engine builder of good reputation. He will balance the crankshaft, rotating components, flywheel and harmonic as a single unit. Don't expect this in an Autozone rebuild and moreso, it can't be done after the fact without tearing down the engine.